Head bolt question - PeachParts Mercedes-Benz Forum

bgiovan · #1 07-03-2011, 03:36 PM

Finally able to get back into my neverending head R&R and something occurred to me that has me a tad freaked out. Had to get a new cam (picked up new cam and towers for an 85) and pulled the old cam off. As I was taking the towers off, had the sucking sound from the oil that was squirted in the head bolt holes per FSM. The one thing that I didn't bother to ask or find out was "how much to squirt". If say too much oil was placed in the head bolt hole prior to installing the head bolts (and presumable expelling the "extra" out the top), would that necessistate removing the head and cleaning everything again?

Since I have the cam and towers off, now would be a good time. Or does any excess oil expelled "burn off" so to speak when the motor comes to temperature after starting for the first time?

Not saying this will be an issue as I was pretty careful to observe common sense but my first time and well, anything is possible.

Thanks and Happy Independence Day!

leathermang · #2 07-03-2011, 03:40 PM

Who told you to squirt oil into those holes ?
THE FSM ? MB ? or Haynes ?

Threads needing torquing need to be clean and lightly oiled...
that is the standard....
If the threads are tight...how are you going to be able to tighten the bolt down .... you have ' hydrolocked ' them....

There is oil squirting on the camshaft all the time... I do not know where you are worried about oil being ???

Did you replace the valve stem seals during this project ?

bgiovan · #3 07-03-2011, 03:48 PM

I guess you answered my question then. Thanks. If I may ask, when I took the head off originally the same thing occured, when I removed the bolts (some not all) were covered in oil and had a sucking sound like a cow pulling its foot out of the mud when I pulled them.

leathermang · #4 07-03-2011, 04:27 PM

LOL, not many people have heard that cow /foot sound...
If they got the oil from it seeping down because of all the oil on top of the head.. Fine..... if it came up from the bottom because of where the hole went ... Fine...
but you can not have a bunch of oil IN a blind hole when you are needing to get the torque right putting it ON...

bgiovan · #5 07-03-2011, 04:29 PM

Sluuuuuuuurrrrrrrrrrpppppppffffffff. Lovely sound! So, pull the head and reclean the area? Yay.

leathermang · #6 07-03-2011, 04:46 PM

Why would you need to pull the head ?
Stick some non lint rags into those holes..
then use a tap to clean them out... which you would need to do either way.... not a problem..
I guess you could leave the head on and turn the car upside down for it to run out... ??

bgiovan · #7 07-03-2011, 04:59 PM

LOL. I just might try it!

I guess my main concern is that if a hole had excess oil in it, I put the new head bolt in and tightened it, said excess oil would have been ejected out of the hole by my tightening the bolt, in theory got between the block and the head gasket (thus ruining my nice clean gasket mount) and now there is a layer of oil between the block, headgasket and head. Kind of like mayo on the lower piece of bread, before the ham. Make sense or am I over thinking it?

I can use the mity vac to suck out any oil.

leathermang · #8 07-03-2011, 06:03 PM

Here is what I do not understand...
How did you see the part about oil squirting in the FSM...
but not read the part about making sure the threads were absolutely clean by running a tap into them ?
If you had followed standard engine assembly procedure you would not have that oil in those holes when you started bolting down your head.....

If you did stick it together with this kind of oil in the hole...
I would not be worried so much about the gasket due to the oil..
but worried about the gasket due to uneven tightening of the head bolts...

bgiovan · #9 07-03-2011, 07:36 PM

It's probably much ado about nothing. Just remembered the cow hoof sound when I took them out originally to remove the head and thought it was odd. I was very careful and tightened in order. Since I have the cam and towers off and have to retighten the head anyway, I'll listen for the cow and govern myself accordingly.

Any tips on the '85 cam on a '79? Seems pretty straight forward.

Thanks LMG. Have a great 4th.

sixto · #10 07-03-2011, 07:51 PM

You don't hear the sound putting the bolts into oily holes. If there's too much oil, the bolt bottoms and torquing doesn't translate to useful clamping force.

Taking a MityVac to the bolt holes is a good idea.

Sixto
87 300D

leathermang · #11 07-03-2011, 08:07 PM

Are you sure that your rocker followers match the cam metal ?
That is the only thing I can think of off hand which I have read about...
Be sure to renew your cap and locking nut on the valves ....

bgiovan · #12 07-04-2011, 10:14 AM

All good there LMG. In the FSM it shows two different types of rockers, the ones I had on my '80 parts car were the correct ones. Funny you mention the valves, just reading that the springs were stronger on the higher output motors. Guess it's an email to Phil.

barry123400 · #13 07-04-2011, 10:56 AM

Quote:

Originally Posted by bgiovan

All good there LMG. In the FSM it shows two different types of rockers, the ones I had on my '80 parts car were the correct ones. Funny you mention the valves, just reading that the springs were stronger on the higher output motors. Guess it's an email to Phil.

You may get away with it but the original rockers that were on the 85 camshaft should have been used in their identical position on this engine. Each individual cam lobe and rocker wear in a pattern to suit each other. Disrupting wear patterns can increase wear.

On your sucking sound on head bolt removal I personally never remember hearing it on any engine I had removed the head bolts from.. I guess I could have missed it but to me it is very strange.

I would not get too concerned about the valve spring strength difference. These engines in service are not all that high RPM wise.

bgiovan · #14 07-04-2011, 11:04 AM

The cam towers and camshaft are brand new. I need to source some other bs parts, sound like I might need to add new rocker arms to the order. Sigh. But I understand the wear notion and hate to cheap out at the 5 yard line.

t walgamuth · #15 07-04-2011, 11:54 AM

Using the old rockers in their exact location is best practice. If they are mixed up it may result in some extra wear.

I would check clearance after a few thousand miles and again at ten thousand and if nothing looked amiss I would not worry more about it.

I doubt I would spring for all new rockers over it. You can always do that later if necessary.