Howdy all, wanted to share the exciting head gasket experience i had. Long story short ended up into a ton of work, for a bung oil cooler!

Pulled the car in for winter, checked the fluids and noticed my oil had turned... there was obvious signs of coolant mixed with oil, but i knew this just happened as i recently did an oil change weeks before noticing this and the previous oil was fine. Judging by the age of the car and KM i decided lets do a head gasket, inspect all internals, change out lots of seals, add some new bits and have a "fun" winter project.


Teardown beginning, you can notice the rusty coolant spray on the passenger side fender liner. This is where i should have known it was the oil cooler based on location and not the head gasket. But the work continued



Milkshake anyone?




Nothing seemed out of place YET in the top end...

Still looking fine for 20yr old engine with no know maintenance history

Ready to remove the head now

Head removed, honestly not as bad looking as i had hoped for. which is good!





Thoroughly inspected the head gasket, a few areas of concern but nothing stood out...

Carbon cleaning commenced!

Pretty well clean now, hard on the hands i tell ya!

Here's where the fun began. Well not fun, the camshaft had the obvious signs of pitting.


Instead of dropping an expensive cam, or even new cam in. I opted for a used clean cam from ALLMAG, as i dont know the entire history of this engine it wasn't worth investing into a potential grenade.

Nothing out of place in the lower end, other then retrieving my previously broken off dipstick!



New gasket installed, a can of brake clean and it was as good as new.

The real issue here, the oil cooler. This is what caused the coolant and oil to mix. It was completely plugged and coolant found an easier opa

Always looks like a disaster when working on these little buggers

Pulled the super damper pulley off a parts car i had and installed it while i was in here.

Since i was so deep in, i double checked timing and reset it all. Gave peace of mind firing it up for the first time again.

Lower timing marks lined up

Head gasket itself placed in, awaiting the head.

Head all cleaned up, new valve steam seals and a polish.

Was not about to pay a small fortune for new valve cover bolts, the collars are simply removable with a vice and hammer. Once the collar was removed, spent 8$ CAD at a local bolt supply and was back in business. Went with 10mm heads over 8mm in hopes they do not degrade as much.

New fancy 10mm valve cover bolts!

Needless to say, did not take much pictures of assembly from here. The camshaft was swapped out for another OEM used one from ALLMAG, the rockers were inspected and did not seem to have issues sticking, they had no marks, chipping or scoring. Seems as if this is typical delamination of the camshaft, luckily there was no major debris in the engine from this. As pictured above the oil cooler was completely plugged, the coolant eventually worked its way into the oil through here. The cause for the plug was either, mixed coolants or using coolant stop leak (mentioned below).

Once the cooler was swapped out, i replaced the timing chain guides. The chain was left alone as it looked great. New timing chain tensioner, head gasket, head bolts and away we go.

All in all, easy headgasket job, which could have all been avoided by checking the oil cooler FIRST! But had i not tore into the engine, the camshaft would have caught up to me sooner then later. Glad to have serviced all the major components while in here!

 

Rockers ok after running on that cam?

 

Heya, Yes surprisingly, They do have typical 100+km wear but no major marks, chips or scoring. It seems as if only the camshaft was de-laminating mainly on cyl 1-2. Instead of investing into new rockers as well, i opted to fix only the obviously wore part (camshaft) at this point. I figure if all the metal that delaminated from the camshaft went though the engine, rockers will be the least of the concerns here shortly. Oddly enough the cylinder walls had no scoring, and what metal i did find in the oil or crevices in the engine was pulverized into fine material. I have a spare W11 i plan on building within the next year, this block is currently a stand in i hope to keep alive for a permanent rebuild in the future.

 

some good work here sir. what caused the oil cooler issue?

 

One of two things,

A- someone had filled the coolant with that stop leak crap with the gold flakes in it. Upon purchasing it was quickly noted the water pump was leaking, it seems as if they tried to cure that with this.

B- Mixed coolant types turned the coolant to gel and plugged it up. I can assume this to be more accurate as when I previously changed the heater core (that was plugged) yellow coolant came out, yet blue coolant was in the majority of the system at the time.

Basically has led me to refresh and replace almost the entire coolant system and parts. Sucks not knowing the entire history of vehciles!