Newbie With a 1983 G Series Van & 6.2

[Yukon6.2]

Hi
I am just curious about the reason for the Detroit head gaskets?
And are you going to replace the gasket on the other side?
As to bolts or studs...
Remember if you use studs you will need extra room above the engine to put the head's back on.
Thomas

[Bigshankhank]

Hi
I am just curious about the reason for the Detroit head gaskets?
And are you going to replace the gasket on the other side?
As to bolts or studs...
Remember if you use studs you will need extra room above the engine to put the head's back on.
Thomas

I got the recommendation for the Detroit gaskets from the TDP book. Is there a compelling argument against them? And no, I am not replacing the gasket on the other side, no reason to.
I had the stud/bolt discussion with the machine shop where I dropped of the head, and as luck would have it the mechanic I spoke with has worked on 6.2's in cargo vans before and made that exact point, so I'm sticking with bolts.

[DieselDavy]

I'm hoping "More Power" will jump in here and comment on his head gasket recommendation. Maybe JK or Robyn will chime in also.
d

[Bigshankhank]

I'm hoping "More Power" will jump in here and comment on his head gasket recommendation. Maybe JK or Robyn will chime in also.
d

I welcome any advice, I am not a diesel engine builder in my day to day life, more of a motorcycle guy.

Fact is I cannot find a source for the Detroit gaskets anyway, unless its from the same Detroit as Detroit Diesel heavy duty engines (from 18-wheelers and locomotive engines). Everything else I've found recommends Fel-Pro. Again, the TDP books had a section describing the various strong and weak points of the different manufacturers of 6.2 & 6.5 gaskets for use on the six-two and the final recommendation was the Detroit. If I can find them.

[Robyn]

Felpro gaskets and bolts are readily available and top notch parts.

I have always used the Felpro stuff.

When you order the gaskets be sure to specify the year.

Some early 6.2 engines "May" have a slightly different water passage configuration.

It may have been only the 1982 "Red" engines that were different, but compare the old one to the new gasket and make sure all the holes line up.


Before you install the head/s be sure to run a metric tap through the head bolt holes to clean them....clean the threads with brakleen or similar degreasing solvent.

NO OILY GOOP ALLOWED
The new bolts come with a DRY SILICONE on the new bolt threads.

Make sure that the deck of the block is SPOTLESSLY CLEAN ...Also be sure that there are no worn spots in the deck where the stainless fire ring has eroded the cast iron block.
This type of erosion can be seen more near the #1 and #2 cylinders where the block does not have a water passage.

The coolant lays against the block and over time electrolysis can cause etching of the deck near the fire ring.

If the fire ring has eroded the deck the only fix is to machine the block (Not pretty as it means removal and complete tear down)

Be sure to follow the torque specs on the bolts exactly... The bolts come with a nice printed sheet in the box along with the sequence too...

Normally these are a multi step sequence with the final pass through being A 1/4 TURN
(20 ftlb...50 ftlb...then 1/4 turn comes to mind)

The TTY (Torque to yield) bolts are pretty much the best choice on these engines..

[Bigshankhank]

This is all great information, thank you.
I checked and mine has the extra water passage at the back of the head. I also think it has the larger intake valves from the early heads (pretty substantial size difference between the intake & exhaust when I looked at them) which I had thought they stopped using in '82? Maybe because this is in an RV they figured to continue spec'ing them for a few more years.
I haven't had a chance to clean the mating surface on the block. Since this wasn't leaking to begin with (I removed it in order to remove a stuck bolt) I am hoping that there won't be any residual damage to any surfaces.

Different question; should I use anti-seize on the exhaust manifold bolts? Because of clearance issues I couldn't get a socket & breaker bar on the bolts and so had to leave the manifold attached when I pulled the head, and if I ever have to remove the head again being able to remove them with just a combination wrench would make this process easier.