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1995 V940 8-Valve (B230FD) with 269,800 on the clock.
BLUF Question
Is there any solid reason *NOT* to grease the iron block surface before installing the head gasket? I know it's not required; but aside from using a Reinz gasket instead of a Elring, It's the one thing I did differently on this head gasket job.
The problem(s) - The Reinz Gasket only kinda sealed to the head and didn;t stick to the block at all. Nasty oil had seeped into couple of my bolt wells and didn't come out with paper towels. This likely caused false torque readings on my two torque wrenches.
Background
I did a big round of engine maintenance back at the end of October, including a new Volvo OEM water pump, low-mileage cleaned-up head, gates kevlar timing belt, and a general tune-up.
Despite having a prior head gasket successes (B18B, B20E, B230FD B5234T3) this change didn't work out well. After a couple days of smelling coolant and oil burn off the motor, I parked it and discovered that I had oil leaking out intake side and coolant leaking out of the exhaust side of the head gasket. Pretty awful.
I had a prior thread where I reported that the head gasket didn't seal
http://www.brickboard.com/RWD/volvo/1580217/940/960/980/V90/S90/head_gasket_didnt_seal_aww_man.htm
Current
With the return of >40F temperature today, I started examining the problem.
I torn town the top end of the engine and pulled the head off. Here's what I learned.
Despite the torques reading even across all bolts, it took substantially less effort to break some bolts loose. Some extremely nasty oil had seeped down into a couple of the bolt holes. I'm sure that this was part of the problem, but I don't think that it is the only issue. The oily holes don't align with the leaks, but it would have eventually been a problem...
After removing the head entirely, I noticed that it came away *very* cleanly. It's sealed to the head, but there's barely an adhesion mark on the block. I think that this is the evidence of the real problem.
With the exception of my white-block B5234T3 engine, I've always greased the iron-side of the head gasket. I did not do that this time, and I think the lack of grease and the lower quality of the reinz gasket kept it from sealing to the block.
I've rulde out "flatness" problems on the head surface and the block surface.
I've cleaned out the bolt holes with compressed air (nasty stuff) and I'm about to clean the block again.
If anyone knows a seriously good reason to *not* grease the iron block before reinstallation, please post asap.
I'm using an elring this time.
Thanks for any and all advice.
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As I reported, I finished the repair last night, but had some issues getting the car to start. As I suspected, the timing had slipped a couple teeth. Resetting the belt solved the starting and running issue.
I ran the car for a long time at full temp, high throttle. It smoked a bit as the previously-leaked oil and coolant was burned off, but eventually it cleared up and seems to be holding well.
I did discover a small leak at at the thermostat housing, so I'll need to get a new gasket, but I don't seem to be oozing oil or coolant any longer.
I'm still not 100% on the problem but I highly suspect it was due to false torque readings and an incompletely torques bolts.
I will say that this is my 3rd aluminum head job (x2 B230, x1 B5234). Each time I do the 3-stage torque, the bolts almost never groan on the final 90 degree turn. This has always bothered me. On the B5234, I even removed all the bolts, chucked the head gasket, cleaned out the bolt wells and started over with a fresh gasket and new TTY bolts. It's held for more than 2 years. With the prior Reinz gasket, the bolts really never felt tight, despite the torque readings and the 90 turn at the end. I've got to deduce that it was oily bolt holes.
I've got a True-Value Hardware flex-shaft torque wrench and a harbor freight 1/2 drive torque wrench. Both give me the same readings, so I doubt that both wrench are wrong in the same way. perhaps it's oil in the block that I can't get out, perhaps it's something else.
Either way, this job is already looking and smelling better than the last round. Hopefully this will last for the rest of the life of the car.
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Once I put Permagasket on an intake manifold gasket - the vacuum of the engine sucked the gasket in a so that it leaked and the engine ran awful>
In the old days, we painted a used head gasket with silver or gold paint to help it seal.
Grease would be a no-no even torqued down, it would create a space that would allow compression to escape.
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The guide for replacing a whiteblock recommends using a copper gasket sealer. I did that for my C70 - which has been fine for a few years now.
I've had one-ever B230 gasket failure (9 months after a near-overheat). I'd swear I used a thin coat of moly grease on the block-side, but perhaps my memory is failing me and I really did do it dry.
The repair was rock-solid from March 2012 until I deliberately switched heads at my last tune-up in October 2013.
Either way, I put in the new Elring dry
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NEVER place ANY substance on either side of a fresh head gasket......NEVER NEVER
this imo is more than likely the cause of your sealing failure
the iron block needs to be scraped clean. they don't warp. if it ever did and i do not see how the bearings would be so smoked the crank would not turn
it is always necessary to verify each head bolt hole is free of any liquid or you will not get sealing torque for that bolt. liquids do not compress
this is an easy job and you clearly have enough successful experience to get it right this time
what ever possessed you to grease the head gasket? that sounds like a move some of the.... oh help me where is the tail pipe ...bag of hammers for brains posters might do.
the head gasket is made of graphite to help it handle the different rates of expansion/contraction between iron and aluminum.
greasing the iron side changes completely this side of the gaskets adhesion and expansion contraction not mention it pollutes the gasket.
if this has been a policy of yours in past you've been real lucky until now.
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The bimetal B230 is a different kitty from the older B-series redblocks (18/20). Greasing the block was something that was recommended for the all-steel engines. Certainly not an idea that I came up with on my own. But, as you suggest, not recommended for materials that have different expansion and contraction rates.
I'm simply trying to figure out why this gasket failed to seal out of the half-dozen or so that I've done in the past. I was failure sure I used a thin coat of moly on the block-side only, but maybe my memory is lying to me on this point. The prior B230 gasket job lasted a good 18 months and probably would have lasted longer if I didn;t decide to switch heads.
As I posted, I checked a couple of different sources and decided to put it together clean and dry. I also put significant additional effort into making sure those bolt wells were clean.
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hello
i have done this job 2 dozen times and never used anything on the gasket. always installed dry. never had a failure or come back.
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Wow.
I always CLEAN the gasket surfaces with acetone. I think I read somewhere that they should be free from grease or oil.
http://www.unm.edu/~goatman/looks.jpg
Goatman
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AFAIK both Elring and Reinz say to install the gaskets dry. Early BMW 318i's had a sealing problem blew their head gaskets very early out of warranty, and the factory advised using "Copper Coat" on the gaskets they supplied to repair them.
I wouldn't advise grease on any composition gasket. The composite is designed to allow the head to work back and forth on the block.
It's possible that the oil in the bottom of the bolt holes prevented you getting to full torque the first time. Clean and dry holes with a bit of oil on the threads, and under the head bolt washers or flanges is all I'd do.
You mention the head is flat ( straight? ) but is the surface finish also good? If the gasket is well stuck to it then probably it is.
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I went ahead and replaced it dry. Instructions say dry, FAQ says dry. I checked a couple of other sources for the job and none used grease. The B5234 white block uses a copper sealant, but I didn't go that route here, either.
I was extra careful to clean (and re-clean) the bolt holes. Both surface were carefully scrapped with a razor (especially careful with the aluminum head).
I also double-checked the bolt torques with both of my torque wrenches. 15/44 lbs-feet, followed by 90 degrees.
I was a bit unclear as I edited by original post.
The gasket didn't stick to the block at all. After checking the head, I realized that it only sealed to a small area at the corners.
Maybe I could have saved it by re-torquing the bolts, but I wouldn't have been able to confirm that the head was "true"
Unfortunately, I'm running out of daylight. I got the engine all buttoned back up, but it won't start. I figured that I overlooked something - likely I'm a couple teeth off on the timing belt.
Checking if the new Elring sealed properly will have to wait for tomorrow.
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You've got it this time for sure. Sounds perfect.
Get the timing set and let us know.
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