When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Saving a 2008 RDX from a severe coolant leak near the exhaust manifold/turbo
After a 10 day vacation the car seemed to be down on coolant while i was inspecting it for my partner. I topped off the coolant and started it up and saw a lot of white smoke coming from under the hood. The smoke came from the area of the exhaust manifold, however there was no smoke from the tailpipe. No bubbles were bubbling up in the reservoir nor was the oil a milkshake. The transmission fluid was good too.
The car never overheated according to its gauges but it was draining a lot of coolant (maybe 1/5 of the reservoir bottle at a time).
Took it to a mechanic chain and they wanted 4k for a new turbo charger.
I do not suspect the turbocharger as the car builds boost fine without laying down the white smoke. The fuel trims are on point and not overly lean or rich.
The car has 324k km on it but we are not in a position to be buying a new car at this time. My plan is as follows.
Locate the source of the coolant leak (i suspect the oring connection by the exhaust manifold on the drivers side). This would be consistent with the mechanic saying it was leaking by the turbo and with the white smoke seen from the exhaust manifold.
I wanted to document the journey here to see if we can save the car. It drives perfectly otherwise and it is at stage zero in terms of its fluids.
Tonight i will attempt to source the coolant leak which will require the removal of the intercooler and maybe some lines. I get to do this at night in a parking lot as that is where the car is parked. Will email acura for the replacement parts estimated cost and arrival date.
Fingers crossed on this, if its leaking where i think it is then it will just be a lot of determination to fix it. My only worry is the screw for the water bypass line as i do not want to snap it. Will probably buy a new line and replace any other potential leak sites.
Took a look at the car and the coolant leak has reduced a bit it seems. The temperature outside was about 10C colder than it was the day of the major leak. Rad was full, and there were no running issues.
Checked the fuel trims with my code scanner and it showed 1.022 or about 2.2% richer for long term. Short term were about on point as well. No codes thrown.
Removed the intercooler and scoped the lines. I wanted to consult you guys as i didn't really see an active leak when i checked. Took the car on a test drive and we could see the mist of coolant but had a hard time finding where it was leaking from. From the drive I believe i have identified 2 areas where coolant was leaking and one more for me to check later.
My current plan of attack is to use penetrant on the retaining bolt marked as 1 in my diagram below. Then to scope the back of the turbo to see if there is any coolant leaking at the gasket labeled as 3 in my diagram. I will also order a new coolant hardline potentially for the top.
If the coolant leak is less prominent i am tempted to try a bottle of radiator rated stopleak. I have had success with head gasket sealer for minor leaks in my old volvo and was wondering if anyone has had success for smaller leaks in these vehicles.
My partner needs this car later as her work told her she will be more mandatory in person. Hoping the parts are not on a high backorder.
Plan of attack:
1) Get estimates on part arrival dates
2) Check validity of using a sealer
3) Confirm location of coolant leak
4) Receive parts and execute plan of attack Diagram of areas of concern overview of process removed intercooler scope location for checking leak area of pre-emptive maintenance overview of are 2 labeled in diagram overview of are 2 labeled in diagram overview of are 2 labeled in diagram overview of are 2 labeled in diagram Concern with bolt for area 1 in diagram. Will take some effort to remove alternative view for area 2 Concern with bolt for area 1 in diagram. Will take some effort to remove View of area 2 after a highway drive
Will check if it is a coolant leak at the turbo coolant line as marked in 3 of the diagram. Will also check the strength of the clamps for the lines coming off of 3 if possible. Fingers crossed.
Most likely the o-ring on the end of the water by-pass pipe, o-ring gets hard from all the heat in that area. You may see coolant on top the exhaust manifold as it tends to run down over the area where the turbo mounts to the manifold.
The part below looks like the 'water bypass pipe' (ext. man. water outlet connecting pipe), marked as #2 on your graphic above:
Its O-ring appears to be Acura / Honda interchangeable 91316-PHM-003.
The gasket for the 'water bypass pipe' (turbocharger water pipe), marked as #3 on your graphic above, appears to be exclusive to Acura 19524-RWC-A02.
Sent an email to acura for a parts quote. Next time i see the car should be Friday or Saturday. Ill check #3 and the associated pipes connected to it. If im lucky it will be leaking from a bad clamp leading to 3.
When i was listening to the car it almost sounded like fluid was dripping or steaming from the back of the turbo. I am wondering if this is the source of my leak. Seems like ill need to remove the turbo heatshield to check, but it seems more accessible than the water line as #1 or #2.
Will post times and costs when i get the quote for my canadian peeps.
Ordered the gasket for the turbo water line, oring, and the flange nut. Might arrive by monday.
Made a plan to access the rear water jacket nuts (3) by removing the turbo intake pipe. If the leak is indeed their then ill order the top gasket later.
Have a plan to fix it, lets hope the plan matches the issue, and then i can execute it effectively.
Well I found the leak and it does indeed seems to be coming from just below the turbo… i don’t know how as the coolant lines circled as 3 are very clean and it is leaking at the bottom of the housing. The way I see it, it may need a new turbo.
however, some research leads me to believe that I could bypass the coolant lines or use a head gasket sealer like blue devil in it. I have previously fixed head gasket leaks with the stuff and it lasted well.
Has anyone here bypassed the coolant lines for a prolonged duration of time? I will post pictures tomorrow
Started the coolant flush process in preparation for the sealant. A cracked turbo coolant jacket should be sealable with the head gasket sealant. Acura uses an integrated thermostat so I am going to use the blue devil pour n go as opposed to the full strength stuff.
Interestingly the heater core seems to need a bit of throttle for water to flow through. Maybe it was just empty when I was testing. When I do the sealant treatment I’ll do a idle at 1500 rpm for 10-15 minutes, then let it idle for the remaining 50 minutes as per instructions.
Today I am using the chemical flush to clean out the system of impurities, tomorrow I will use the sealant treatment.
Ive seen this stuff work well on compromised heads, and a cracked water jacket for the turbo would see the same temperatures so fingers crossed it will work.
Replaced the o-ring on the turbo water inlet but it still leaked. I eventually tried using K Stop Leak and it looks like it has worked. No more refilling the reservoir and I don't smell coolant in the garage after driving.
I was weary of using a stop leak but based upon Chopperpilot and my experiences, it seems to work.
Finished doing a chemical coolant flush in preparation for the stop leak.
Purchased a spare thermostat and have elected not to remove the old thermostat from the housing. Ensured the heater core is clean and full of water and will run the blue devil pour n go in the morning. Fingers crossed!
Used the sealant and drove around a bit. Car sounds a little bit quieter and turbo almost feels a bit more responsive. Had a fuel pump open circuit come up after starting the car which caused it to stall. Gave it 5 minutes and tried again and it fired right up.
the smell of coolant is much lighter if not gone, however that could be caused by me switching to distilled water to use with the sealer. Will let the car cool and see if it lost a lot of coolant, and if it’s still leaking at the same spot. Fingers crossed and will give an update in a few hours.
Just refilled with new coolant. Noticed the level changed a bit and will leave it overnight to see if its a drastic change. I no longer have a leak at the turbo nor do i have steam coming out the tailpipe in any capacity. I can still smell some burnt coolant but could not locate a source. Small bubbles were coming up into the overflow tank so we will see.
Going to swap cars with my partner for the week and put the car through its paces (probably around 2-300 km). Will monitor coolant levels and see how it performs.
Maybe i will need the coolant o ring and the gasket after all? My best case scenario is its a pipe, and moderate scenario is a water pump change.
Looks like this car will live a bit longer though.
After the 124 km drive it seems that the coolant level changed very little if any. This was a marked difference from earlier where a 5km drive would drain half the overflow bottle.
Will mark and measure the return trip later. Will keep a spare bottle of coolant in the car at all times.
Checked this morning and no further coolant losses. At this point i considered it solved. Will monitor if a further issue persists. Thanks dP- & chopperpilot for reporting that a similar fixed worked for you as well.
Summary:
Theorized hairline crack for coolant passage within the TD04 turbo was leaking coolant into the exhaust and out of the housing. Headgasket sealer will leave a glass like deposit when it evaporates through cracks thus sealing up the leak. Seems like the hairline crack was between the larger housing and coolant jacket as the turbo is noticeably quieter now. Ensure you flush your coolant system with a cleaner prior to doing this to avoid any crystallization.
you handled the coolant leak like a champ. I am probably going to need to do the same thing on my car. My car also had a coolant leak. originally DX as an o-ring on the exhaust manifold, but it's something worse than that. probably a bad turbo. Strange that I still get no fumes in the coolant when tested.
I was tipped off when I looked under and only saw coolant coming from the exhaust housing of the turbo. My understanding is that it probably does not have the pressure to push into the already pressurized coolant system. what I got instead was more of a leak that you see when you have a split pipe or bad o ring. I think eventually I’ll change the water pump as it looks like the reservoir went down 5mm over 250kms but that is something I can live with. The odour of coolant is gone from the interior and the exhaust is no longer damp after a drive.
i would flush your coolant system fully with a chemical flush. Only keep that stuff in there for a short time. I did a half hour and flushed twice with distilled water. Once cleaned out, your coolant is much less likely to react poorly with the sealant. Then do the sealer treatment. I prefer blue devil or k seal as it has less particulates and reacts more when the coolant is forced through a crack/evaporates. That was the exact issue I faced with the turbo.
one other thing to note, a leak on the exhaust side may affect turbo performance in terms of seal, and may affect your o2 sensors. I would reset your idle, and maybe even transmission adaptation as the power curve may change slightly.
thanks for sharing. great write up. My RDX is going through a lot of coolant now, and I still have not seen pools of wet coolant or any white smoke buring, which is bizarre. I'm gonna do a seal treatment and see what happens. If that fails, i'm probably pulling the engine, or buying an engine to build.
05-28-2024, 06:10 PM
