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I'm thinking of valve lapping as a way to mold the valve to the valve seat. Am I correct in thinking that way, or is that wrong?
Regardless, the guy at the machine shop told me that the valve seats should still be good. But I'll be finding out soon enough. Just gotta turn the car 180° some how..
the hand grinding is sometimes used as a finishing step when valve seats are still good and only minor wear is present on the valves. its not really going to restore the valves. maybe debur at best.
Motor is out. Took me 3 days. Had to remove the bumper and the frame of it to be able to get the hoist chain to hover over the middle of the engine.
I did the same thing I did at the junkyard. I forgot one more transmission to motor bolt. Was one on the back that was hidden. Transmission is now sitting crooked in the car. I'll have to use my jack to sit it up straight later.
Valve spring compressor tool is set to be here tomorrow. I'll deal with cylinder head removal tomorrow. Too tired to fuck with head bolts right now.
Oh, and I recorded everything. So I'll be posting a video in the future on my channel. Not as a tutorial, but because I was bored and wanted to.
Last edited by Thefireball; 09-15-2021 at 03:32 AM.
Nevermind, fixed the transmission being crooked. I just jacked it up and reinstalled the mount to hold it.
I do have another issue that has been plagueing my car for awhile. Y'all have any tips on installing the header-to-Jpipe gasket? The front one is the original one that came with the DC Sports pipes, but the manual said to use OEM Honda gaskets. The front is in there just fine, and has been in there since I installed them. But the rear one just never seats in it's space correctly. They always are mangled, and I don't think they're sealing properly.
I'm thinking to maybe take my Dremel and just grind the space to be a little bit bigger, or maybe heating up the gasket with a torch, then installing it?
Last pic is the front pipe with the gasket installed. Kinda hard to tell.
^
For better sealing, one way to have more 'control' over positioning of the gasket on the flange would be to make one using some kind of 1/16th thick exhaust gasket material.
That way you could use the bolt holes for positioning and the gasket would be easier to fashion with the engineless access you now have.
Pulled the cylinder heads off, and got to take me first look at everything. I'm still not sure what to make of everything, so start throwing out what you think happened.
Upon taking a look at the motor, everything looks normal.
It was when I began cleaning up the pools of coolant in the cylinders that it became very apparent.
Let me first say that I made sure these cylinders and heads and everything was cleaned off before installing the heads.
Now, as you can see, there's a lot of dents in that piston, but even worse, there is a scratch in the cylinder wall that my nail is able to catch. Not good. That piston is done, and now the block too. Every other piston & cylinder is a-okay, except there was a very very small chunk of metal that indented and stuck itself into piston #4, but pulling it out, you can't even tell there's a dent. So that piston is fine in my book.
Now onto the heads, and this is where it gets worse.
Now, after having seen the pistons, you'd think it'd have bent the valves, mangled them, and thought that the valves we're the culprit for the dents in the pistons, but from what you can see, they look unscathed. Again, I cleaned everything before installing the heads. From the looks of it, something got into the cylinder and wreaked havoc. I didn't find anything in the motor or heads, so I have no clue what it could have been. What I will say though, is that installing heads with the motor in the car, sucks. Being that this is the bank of rear cylinders, and installing the rear cylinder head was the most difficult one out of the two, I'm guessing that's where things went wrong.
Now, the valves look untouched, on both heads. While one cylinder head is now garbage, the other still looks fine. I obviously need to check for warpage, and if any of them are leaking. But just looking at them, they look fine. I can probably just remove the valves and reuse them on my other set of heads that I have. But, I think I'm just going to order a used set of J32A2 heads for now, to get the motor built and my car back on the road, and experiment with rebuilding heads in the mean time.
Last edited by Thefireball; 09-18-2021 at 04:24 AM.
wow, odd that the damage is only to the edges of the piston. small debris can sometimes blow out the exhaust outlet. hard to speculate what it could be from the top down pic. i would want to see the side of piston. maybe the ring lands started cracking.
wow, odd that the damage is only to the edges of the piston. small debris can sometimes blow out the exhaust outlet. hard to speculate what it could be from the top down pic. i would want to see the side of piston. maybe the ring lands started cracking.
As soon as I get an engine stand, I'll start removing the pistons and find out, unless I find figure out another way to flip the motor over.
Small update though. I flipped both heads over, after installing spark plugs, and poured naphtha into the valve cups. So far, the only leak is coming from both intake valves on the cylinder with all of the dents. Exhaust valves aren't leaking for that cylinder. I'm going to let it sit overnight (or morning; I'm a night owl), and see if any leaks form later.
The yellow/brown trails are the naphtha leaking through, being stained by the oil.
**Update: one more intake valve started leaking on cylinder #3. (The blue trail is not the naphtha. It was there before doing this.)
Last edited by Thefireball; 09-18-2021 at 04:51 AM.
I hate posting multiple times, but I just wanted to fix and clarify something. I had the motor backwards, and got the cylinders confused. The cylinder with the dents is cylinder #4, so the front bank. I'm surprised I messed up the easier of the two head installations. The new valve that is leaking on the second 'good' set of heads is cylinder #3.
That's crazy.
Did you notice if there was any type of debris collected or rattling in the cat converter?
One would think that something may be there or in the oil pan.
That's crazy.
Did you notice if there was any type of debris collected or rattling in the cat converter?
One would think that something may be there or in the oil pan.
I can't remove the J pipe since it's welded on to find out. I guess I could shake it around though. I'll find out what's in the oil soon enough.
on that bad cyl, there was nothing wrong with the spark plug?
I don't exactly remember, but I think I would have mentioned if there was a problem with them (I sound rude saying that; not my intention).I think all I found was a white looking spark plug in one of the cylinders.
Update on leaking valves;
No more valves are leaking, other than the ones I posted. The naphtha is completely drained on the #4 dented cylinder head, naphtha is halfway drained on cylinder #3. The rear cylinder head can probably get away with just a replacement valve. I'm going to try out this same test with the other set of heads, since it tells me which valves are bad.
So, some questions, along with my findings.
I've gone ahead and taken apart one cylinder head fully so far. It's a head off of the third junkyard motor I pulled.
- Almost every exhaust valve seat looks pitted, and a couple of intakes.
- Every valve seat looks visually fine; straight cut, and no rounding, with 3 dimensions. Still waiting to take actual measurements with the correct tools.
- I don't know if this is indicative of anything, but if I plug the end of the valve guide with my finger, and pull the valve, every single one will seal, and even pull the valve back.
- Some of the valves get 'stuck' in place. So much so, that I was pushing so hard on an exhaust valve, it eventually had so much force to jump out of the head. Every intake valve pushes up fine, no problem, but I counted 3 exhaust valves that needed excessive force to move up. This is with them cleaned up with brake cleaner & a rag, then lubed with WD-40.
- I've read that with a good valve seat, you should push the valve with some force behind it, and it will bounce back up. None of my valves even move after letting go. As in, going down. I have to push them all the way down with my finger. No bouncing. This is with a generous amount of WD-40 in each valve guide and on the valve stem as well.
Is this all sounding right? Like, everywhere I've read, the valves should bounce, but mine are not smooth moving. Like, they'll push in just fine with my finger, but they do not have any 'freeplay' movement to even consider bouncing them off the valve seats. Not to mention the fact that those 3 exhaust valves actually stick in place.
I'm guessing every valve guide on this head is good, should probably take another closer look which I will do later. Any tips on what to look for, and what to test?
Last edited by Thefireball; 09-21-2021 at 04:37 AM.
Without pics its hard to speculate. probably carbon buildup in the valve guides. A 5.5mm reamer is mentioned in the service manual. But, the context is after the guide replacement procedure. Found this as well:
Check the clearance with an appropriate valve. Verify that a valve slides in the intake and exhaust valve guides without exerting pressure
You did take the valve seals out right?
Without pics its hard to speculate. probably carbon buildup in the valve guides. A 5.5mm reamer is mentioned in the service manual. But, the context is after the guide replacement procedure. Found this as well:
Check the clearance with an appropriate valve. Verify that a valve slides in the intake and exhaust valve guides without exerting pressure
You did take the valve seals out right?
You're telling me that little piece over the guide can come off? Well shit. Do I feel stupid.
So, I have just finished replacing all the exhaust valves with the ones from the rebuilt head, mainly because they were newer and I couldn't put a suction cup on the worn ones. I also just finished lapping every valve. The first head off of the third motor is now able to hold gasoline in every chamber with no leaks. Took me a couple of relappings on some valves to get it down correctly, but it's all good in that department now. Every valve is free moving, bounces off the seats, and there's little to no wiggle in the guides. I'm going to leave the resurfacing to the machine shop. As much as I'd enjoy doing it myself with a flat piece of glass and sand paper, I'm good.
However, I did come across something. I'm not sure how or when this happened, but it's a bit concerning. There's a nick in the side wall of the head, next to the chamber. It's not too big, but it has a sliver of metal hanging inwards toward the valve, and a dent that might cause a leak. I'm considering just using a Dremel to get that hanging piece of metal out, and hoping it'll be fine once it sandwiches a head gasket. What do you guys think?
Getting a pic with my macro lens was hard due to the flash reflecting off of it, and no flash was too dark too see.
And lastly, is it alright to reuse the valve seals? I was considering reusing the ones off the rebuilt head. Not like they're expensive; I can just order more. But if it's fine to reuse, why not?
Last edited by Thefireball; 09-24-2021 at 03:03 PM.
I did come across something. I'm not sure how or when this happened, but it's a bit concerning. There's a nick in the side wall of the head, next to the chamber. It's not too big, but it has a sliver of metal hanging inwards toward the valve, and a dent that might cause a leak. I'm considering just using a Dremel to get that hanging piece of metal out, and hoping it'll be fine once it sandwiches a head gasket. What do you guys think?
And lastly, is it alright to reuse the valve seals? I was considering reusing the ones off the rebuilt head. Not like they're expensive; I can just order more. But if it's fine to reuse, why not?
I wouldn't chance using a dremel on that, just let the machine shop mill the head. Also, don't reuse valve seals, they're relatively cheap and keep oil from leaking into the chamber. You don't want to rebuild it and find out you have to tear it apart again to fix an oil leak.
I wouldn't chance using a dremel on that, just let the machine shop mill the head. Also, don't reuse valve seals, they're relatively cheap and keep oil from leaking into the chamber. You don't want to rebuild it and find out you have to tear it apart again to fix an oil leak.
Machine shop it is. I didn't realize how cheap the seals were until I checked. $11 for all 24 from Florida on rockauto. I think I'll take that deal.
On a side note, lapping valves is extremely satisfying. Honestly look forward to doing the next head.
Motor is now on a proper engine stand. Was a pain to get on, and the mounting points are positioned badly, but it works and holds.
Block has been checked with a precision straight edge and a .005mm feeler gauge. It didn't slip through anywhere on both sides. So block is good.
All valves have been lapped, and cylinder head has been dropped off at the machine shop Thursday to be resurfaced. I'll be reusing one of the rebuilt heads and it's still in good condition, and doesn't need to be resurfaced. I also checked it for warpage, and although I didn't have a .002mm feeler, the .005mm didn't slip through anywhere.
Some small rust spots began to form in the cylinders, so I scrubbed them off with a wire brush & degreaser, then wiped them dry with a microfiber towel, then greased them up with assembly lube and covered all the cylinders with clean dry microfiber towels in hopes of preventing the rust forming again.
Also picked up a pressure washer with a bad pump (as well as 3 broken weed eaters) off of Craigslist. Got the new pump, just need to install it. Going to clean the block as best as I can with it.
Now that I have the motor on a stand, I was paying attention to the cylinders them selves, and there's some dark spots, and very very slight scratches on the wall. Not enough to stop my finger nail running across it, but I can feel it. I figured I might want to hone all the cylinders, and if I'm going to do that, I should replace piston rings & bearings. Checking rockauto though, there's different options to go with regarding size, and I'm not sure what I need to get.
Should I just go with standard rings and bearings, or go over sized? What do I need to do to check? Should I even bother honing? Figured since I've come this far, I might as well make sure everything is covered. I can still see the cross hatching on the walls, it's just those couple of scratches that concern me, even if they're not deep.
Last edited by Thefireball; 10-23-2021 at 01:44 PM.
Here I go again, doing what I hate; double posting.
But I just wanted to say that I always forget that the manual tells me everything I need to know, regarding what to do & what to check. So the real questions I just need to know are:
• Should I bother honing? Are the light scratches going to be a problem in the future?
• When should you use oversized bearings & rings?
Here I go again, doing what I hate; double posting.
But I just wanted to say that I always forget that the manual tells me everything I need to know, regarding what to do & what to check. So the real questions I just need to know are:
• Should I bother honing? Are the light scratches going to be a problem in the future?
• When should you use oversized bearings & rings?
Oversize bearings are for when the crankshaft is machined. It makes up for the materials removed. Similarly, oversized rings are for when the cylinders are machined, to make up for the difference. The main reason to go oversized piston is due to excessively worn, damaged, tapered or out of round cylinders. This should be determined by taking measurements on all the cylinders at different spots and comparing to specs. i.e if the wear is not out of spec, there should not be a need to go oversized. I believe the J32 is an iron sleeve, which has more flexibility with pistons than a nikisil coated / frm cylinder. But Honda/Acura did not leave much excess material for boring. Maybe .50 at the most.
As with anything auto related performance and durability are a trade off to cost. So. if you must replace pistons or bearings, try to use o.e. or good brands.
It's a judgement call on the honing. I have not machined or bored a J yet, but can tell you I have had a frm h22 honed to o.e. size and it lasted about 30k miles with MAHLE high compression pistons seeing heavy abuse and a 75 shot of nitrous. On the other hand, I've also skipped a hone on a high mileage h22 and used ebay type s pistons and the motor seized in under 10k miles.
For my project 6GA j32, since the motor is so high mileage, I'm actually thinking of ordering a brand new block from Honda to avoid any boring, machining or oversize parts
- I've gone ahead and replaced all the rod bearings with brand new ones. Old ones were worn, but didn't show any copper layers, and some light scratches. Nothing that caught my finger nail anyways. So not worried about the crank.
- Brand new valve stem seals, one head was resurfaced since the other was fine. Checked both of them with a precision straight edge and feeler gauge; perfect.
- Replaced a couple of worn valves with new ones that were from the previously rebuilt head that was damaged. Lapped every single valve in both heads. Made sure to keep every valve to the ones they were originally lapped in.
- Cleaned everything vigorously and meticulously with brake cleaner/carb cleaner, and multiple microfiber towels. Cleaned everything from crank, bearings, valves, seats, guides, to the inside of the cylinders and pistons, to even the mating surfaces of both the heads and block.
- Lubricated everything with assembly lube.
- Heads are now on with a brand new head gasket and TTY bolts, torqued to spec, in the correct sequence.
I've gone ahead and done a compression test, and well, I don't know what to do. It's able to make more compression than it was able to when I first brought the motor home. I believe it was simply just carbon build up clogging the valves, and preventing them from closing all the way.
Regardless, PSI wasn't that great. Lowest I got was 58 psi on #1. Highest was 112 psi on (I think?) #6. Most cylinders floated between 60 psi and 80 psi. I figured maybe there was foreign material on the valves, so I sprayed some WD-40 on all the valves, enough to also help with lubricating the cylinder walls a little bit. It was originally getting 38 psi on #1, until I cranked quicker by hand. I could also see wear the leaks were coming from on the intake valves, as they were bubbling and spewing WD-40 everywhere upon the compression stroke.
What I'm wanting to know is:
- Is hand cranking effective, or do I need to use something like the starter motor to crank it quicker?
- Should I just take the heads off, and have a machinist take a look at it?
- Does it need a break in period/heat cycles to cause the valves to properly seal? It was pretty cold in my garage; enough to see my breath.
Last edited by Thefireball; 11-06-2021 at 03:44 AM.
What I'm wanting to know is:
- Is hand cranking effective, or do I need to use something like the starter motor to crank it quicker?
- Should I just take the heads off, and have a machinist take a look at it?
- Does it need a break in period/heat cycles to cause the valves to properly seal? It was pretty cold in my garage; enough to see my breath.
I didn't notice mention replacing rings, or if you added assembly lube and or break in oil. you're probably not going to get good numbers hand cranking a rebuilt motor without proper lubrication. oil on the cylinders, rings, valves is necessary to make a good seal. likewise its probably not a good idea to rotate a dry engine for very long. normally with a rebuild, i pre fill the oil filter, use assembly lube on all the internals, add a quart of break in oil in substitute for one quart, then when ready crank the engine with the ignition disabled to prime the pump.
I didn't notice mention replacing rings, or if you added assembly lube and or break in oil. you're probably not going to get good numbers hand cranking a rebuilt motor without proper lubrication. oil on the cylinders, rings, valves is necessary to make a good seal. likewise its probably not a good idea to rotate a dry engine for very long. normally with a rebuild, i pre fill the oil filter, use assembly lube on all the internals, add a quart of break in oil in substitute for one quart, then when ready crank the engine with the ignition disabled to prime the pump.
I decided to leave piston rings alone. More than likely not the best idea, but I figured it'd be best to leave well enough alone after checking the bearings. Bottom end was dirty, but over all, seemed fine.
Dry cranking is a concern of mine, but when I do crank it, it doesn't feel 'dry' or like anything is rubbing. Everything still moves smoothly.
Valves are definitely leaking though, I can see & hear it happening.
Well, I mean I'm already this far. Should I go back and do the rings? Now I'm worried .
Motor is in the car, and bolted up to all of it's mounts. Connected to the transmission. I had some issues bolting things to the flywheel, and ended up having to disconnect a couple of times. Motor has plenty of oil in it.
Finally did a proper compression test using the battery from the Lexus and some jumper cables on the starter motor.
1. 143
2. 165
3. 188
4. 161
5. 164
6. 187.5
It's clear that cylinder #1 is not within that 25 psi limit, nor is #4. Is it worth it to continue bolting the motor up? Perhaps it needs to be broken in? Numbers will be different once the motor is warm, and clearances will be met, but still out of that 25 psi range has me worried slightly.
I guess I could try removing the rear head and relapping all the valves & checking seats again, or maybe having the machine shop actually fix the problem, but will I need a new gasket & bolts? Or could I just reuse what's on since the motor hasn't actually been started?
Honestly tempted to just say screw it and continue. Been waiting long enough. The Lexus blew a head gasket, and I'm having to borrow a car currently, so I need something fixed at least.
Honestly tempted to just say screw it and continue. Been waiting long enough. The Lexus blew a head gasket, and I'm having to borrow a car currently, so I need something fixed at least.
I realize this is easy for me to say . All the more reason to forge ahead, IMHO.
Good Luck!
can't reuse a head gasket. Although its not preferred, you can reuse head bolts, just leave in the same spots. As to the low compression, its definitely low on #1. But it is a used motor, so who knows? there is a chance it may go up with oil, but it really comes down to how it runs.
At least it's making compression. Suppose I'll chug along and continue. Not too much else I need to do. Maybe another night or two until I can get it started. Just gotta stop being lazy.
I was working on the car just now, about to get it ready to start, but I made a discovery. It explains what happened to the original J35 motor, and where the knocking noise came from. It also explains why it would knock, then stop knocking, then knock again. The problem is, I don't know what it's from, where it came from, nor where to look. I refuse to continue putting things together until I find out where this came from, because I don't want to destroy ANOTHER engine.
As you can see, there are LITERAL CHUNKS OF METAL INSIDE THE INTAKE MANIFOLD WHERE THE BUTTERFLY VALVE LIVES. It's not just in one chamber, it's in every chamber. The picture first shown shows the chamber with the most. The others aren't nearly as bad, but it shouldn't be there in the first place.
Every bolt that holds the IM onto the runners is intact, including the two nuts. The throttle body shows no visible signs of damage, nor scratches. Intake tubing showed no signs of damage or scratches, nor did the filter.
If you look at the images, you can see that one of them shows the chunk metal being rounded. Call it a clue, but I don't know what piece of metal matches that curve. But the bigger question here is; what the hell caused it to break apart within the intake manifold?
Any ideas what this is, where it came from, and where to look? I'm going to go ahead and clean the intake manifold for tonight.
Everything after sifting it.
None of it is magnetic, except the original curved chunk of metal I showed. It's not from the spark plug that was smashed in on the original J32 motor; I checked.
Could that be a bottom piece of the metal cylinder lining that somehow found its way up to the IM chamber?
How would it get into the IM though? I'd like to split the IM in half and take a look at it, but I already tried once and it won't without breaking it.
How would it get into the IM though? I'd like to split the IM in half and take a look at it, but I already tried once and it won't without breaking it.
Just a guess.
For 'grins & giggles', take that piece and try and match it to the radius and thickness of the cylinder liner, at the yellow indication, on the picture below?
Just a guess.
For 'grins & giggles', take that piece and try and match it to the radius and thickness of the cylinder liner, at the yellow indication, on the picture below?
That motor is long gone. It don't doubt it came from the piston & liner. I guess that explain why some chunks are magnetic and others aren't.
Only way I can make sense of it getting into the IM is that since there was a giant hole in the piston, there was just no air being sucked into the cylinder, and so it was just pushing the metal through the bent valve, where air was being sucked into other cylinders, so it pulled it up into the manifold. My best guess.
Looks to be something cast aluminum. Perhaps the grenaded piston was breaking apart and was pushed out the intake with the blow by. My guess is pre ignition from carbon build up on the piston.
I'm very happy right now. Very very very happy. So relieved. I just needed to post about it, even if it is a bit early.
I finally started the motor. I cranked it first without coil packs in, just to see what would happen. Everything was fine. So I plugged them in, and started it.
Things weren't great at first. Not misfiring, but the idle was a bit wonky. To be expected with wonky cylinder pressure. At the same time, lots of white smoke out of the exhaust, normal after a rebuild I'd say, plus it was really cold out. But I let it sit and idle for a bit, and let the motor warm up. Idle was at the exact RPM it should be sitting at. All good there. CEL and VSA are on, I'll figure it out.
But then it finally starts rising in temp, and it all settles out. The exhaust sounds normal.. it sounds great. The motor sounds healthy, and there are little to no vibrations with the engine. I haven't revved the motor yet, I simply let it idle. But so far, I'm extremely happy to know that my work hasn't been for nothing - yet.
I'm going to start it up again later, let it warm up again, and then try a compression test again after the motor is warm and post the results here later. I'm just too happy to not post about it right now.