Head shim

[rat4020]

I have a 08 Apex with a GT2860 intercooled and running about 10lbs boost in a Off road car . Last fall runnin the corn fields in noticed dust was colecting around the motor but I didnt think too much of it . The last two weeks I have been riding down in Cali in Glamis sand dunes , the motor ran perfect . But when I returned home there was a few drips of coolant under the rt rear it apeers to be comin out the head around the rt rear about two in over to the left . My exaust and plugs look as they should with no overheating . My question would be just how long is the head shim good for mines 3 years old . And I was thinkin just replace the shim with a new one .
Thanx for any reply's

 

[ghost rider]

Cool combo ... Must be a blast to pilot,
I run the same boost as you with a five year old gasket ... No issues so far
however there are far more experienced turbo gurus than I that
can speak to longevity... Coolant leakage is a sure sign of pending problems imo.

 

[rat4020]

Thanx for the reply ghost .. Ya its a total hoot to pilot it was fun before the turbo but its a heavy car at 1500lbs + and with the addition of the extra 90hp there aint a dune it wont pull 55mph up in Cali or ID even with a fat friend ridin Copilot . I have some vids on my YouTub channel https://www.youtube.com/channel/UCHhj1CRmgfmot5n5Iblny1g
Since I posted this tread Allen called me & advised me what to do and check .

 

[ghost rider]

Cool videos, looks like a blast....your suspension looks killer lots of smooth travel
I've only ridden snow dunes.
I'm a stock engine carb guy so your set up is not in my scope...
Plenty guys here that are very tech savvy certainly with head shimming.
Good luck and keep posting those vids.
I subbed your YouTube channel I'm listed as ... smash editorial

 

[rat4020]

Thats Cool Ghost Rider . Here is a fresh dunin vid from two weeks ago in So Cali . The motor sure sounds great

 

[rxrider]

The shim should last the life of the engine.
It may be that the head is not tighten Down enough and the gasket has failed.
If you change the shim I would recommend that you also install ARP hardened 10 millimeter head studs.
The Stock head studs can only be tightened to 50 Nm.
The ARPs spec is 60 Nm.
I have never seen a gasket or head shim let go With ARP head studs tightened Down at 60 Nm.
I have seen a few running Stock head studs let go and starting to leak.

 

[rat4020]

Thank RX for the reply
I do hav the ARP studs and I taped them out to the very bottom
I'm going to back off and retorque the head as Allen said

 

[rxrider]

Yeah. I always back them off 1/4 turn then tork back to spec at 60 Nm.
Always tork them in the sequence Yamaha says in the Service manual.

 

[rat4020]

Thanx RX been a while since I heard from ya
I will be retorquing them today

 

[rxrider]

I tork them in Yamaha sequence, first to 20 NM, second to 35 Nm, third to 50 Nm, and finally to 60 NM (With the ARP studs, With Stock studs 50 Nm is the limit)
Back off 1/4 turn and tork back to spec, all in the proper sequence.

I've been very busy for the last year at work and privately leaving little time to contribute on the site.
I hope to spend a little more time on TY for the reminder of the season, at least until May 15th when Our season ends.

 

[rat4020]

Torked them just as U said RX and finished it up & ran it on sat for a good 2hrs every thing is good . BTW the bolts were not to spec .. so I guess live and learn .. right