1985 300TD head gasket repair - PeachParts Mercedes-Benz Forum

Chad300tdt · #1 09-14-2012, 02:03 PM

The head gasket on my wagon is shot. Oil in the coolant and coolant in the oil.

I drained the fluids and started taking it apart. I also bought all the gaskets and seals to do the head gasket, turbo and oil returns, water pump, oil filter housing, and a trans filter and pan gasket.

I have the manuals, and most but not all the tools needed. I don't have the prechamber or timing chain tools and there may be others I need that I'm not aware of.

I'm hoping to find someone willing to help me with this job. I want to make sure I do everything correctly and an experienced second set of eyes and hands would take away all my apprehension.

Proper removal of the head, prechambers, and timing chain elements so I can send the head out to a machine shop to check it would be step one.

Then another visit for reassembly.

Is anyone able to help me out with this? I'm able to compensate the person and we can work out the details to make it worth their time.

I REALLY need to get this wagon back on the road before winter since my SDL doesn't like the cold and the wagon was always a reliable winter car prior to this.

Chad300tdt · #2 09-14-2012, 02:51 PM

Here's the work space.

Parts waiting to get installed.

Removed parts.

The evidence.

gatorblue92 · #3 09-14-2012, 03:19 PM

I have no experience but am willing to help.

TheDon · #4 09-14-2012, 03:39 PM

Get te triple square tool from either hazet or stahwhile if it's required.

Chad300tdt · #5 09-14-2012, 04:14 PM

Quote:

Originally Posted by gatorblue92

I have no experience but am willing to help.

Thanks for the offer, but my brother can help with labor like lifting the head if needed. I really am looking for someone who will know all the possible pitfalls in this job and how to avoid them.

You're welcome here anytime, I just don't want two inexperienced guys (head removal) trying to figure our way through it.

Quote:

Originally Posted by TheDon

Get te triple square tool from either hazet or stahwhile if it's required.

I have a set of hardened triple square bits that I bought for my hatch struts. I was planning to use them with the hopes that they won't spin off. If they do, I guess I'll go for the higher end bits. I'll make sure the bolt heads are spotless and the bit is seated properly.

79Mercy · #6 09-14-2012, 04:26 PM

You'll prolly need a engine hoist to lift the head off the block, its gonna be stuck. I used a engine hoist when i did my M110 head and it made life so much easier.

Also here is another tip for re-installation that i didnt think about in the PM.

I took 5 or 6 of the old head bolts and used air tool to cut the heads off the bolts. I also cut slots in the top for a screwdriver. I screwed them into the block and used them as guides when i went to lower the head back down on the block. Those were a HUGE help.

compu_85 · #7 09-14-2012, 04:32 PM

Ya, the cast iron head weighs a lot more than you expect it to. A hoist of some sort will make things a ton easier.

-J

whunter · #8 09-14-2012, 06:43 PM

Quote:

Originally Posted by Chad300tdt

The head gasket on my wagon is shot. Oil in the coolant and coolant in the oil.

I drained the fluids and started taking it apart. I also bought all the gaskets and seals to do the head gasket, turbo and oil returns, water pump, oil filter housing, and a trans filter and pan gasket.

I have the manuals, and most but not all the tools needed. I don't have the prechamber or timing chain tools and there may be others I need that I'm not aware of.

I'm hoping to find someone willing to help me with this job. I want to make sure I do everything correctly and an experienced second set of eyes and hands would take away all my apprehension.

Proper removal of the head, prechambers, and timing chain elements so I can send the head out to a machine shop to check it would be step one.

Then another visit for reassembly.

Is anyone able to help me out with this? I'm able to compensate the person and we can work out the details to make it worth their time.

I REALLY need to get this wagon back on the road before winter since my SDL doesn't like the cold and the wagon was always a reliable winter car prior to this.

Great talking with you on the phone.

Best of luck on this DIY.

.

charmalu · #9 09-14-2012, 07:01 PM

First head I removed was after my timing chain feasco back on 09. read the Haynes book to get an idea of what to do. then talked to my indy.

Bought a tripple square bit off the Matco tool truck, at least I had a good one to start with. to get the head loose, (after the bolts are removed) the haynes book said to whack it with a piece of wood/hammer. did not want to budge. My Indy said to slip in a prybar under an edge and pry up, think it was on the front side. just went out and looked at the eng and cant`t see or remember where it was. but lifted the head up and broke the seal.

I then man handled it off the engine. think it weighs 100lbs.

be careful, those things can hurt you. I didn`t have the hoist at that time, now I have 2.

Charlie

Chad300tdt · #10 09-14-2012, 07:23 PM

Thanks for the tips guys. It's appreciated.

Special thanks to whunter for taking the time to walk me through the job on the phone. It was great talking with you as well.

Chad300tdt · #11 09-17-2012, 03:58 PM

Today I bought a parts washer and a metric tap & die set.

I also removed the thermostat housing, fuel injector lines and injectors, and the glow plugs.

More parts removal tomorrow as I get closer to head removal. Everything has been fairly smooth so far* and I should be able to work on it 3 hours a day and all day Saturday.

I'll post updates and photos as I dig deeper.

*A large puddle of trans fluid appeared on the floor under the car, so that will have to be looked into later too.

79Mercy · #12 09-17-2012, 05:12 PM

Macdoe, yes that could be a problem however i did have a solution to it.

Get the cylinder head about 4- 5inches away from the block hanging on the hoist. Take the modified bolts(head cut off) and slide them through the TOP of the head and position the head so that you can screw the stud into the correct hole. Doing it this way eliminated the potential of damaging the new head surface.

Chad300tdt · #13 09-18-2012, 03:43 PM

Today I removed the alternator belts, fan and pulley, shroud, power steering belt, power steering/fuel filter bracket, hydraulic pump, rocker arms, guide rail pin, tensioner spring, and marked the chain & sprocket, removed sprocket with impact gun, pulled the chain off the sprocket and put the sprocket back in place for now. The chain is tied off to the alternator bracket with zip ties.

Enough for today. Tomorrow will be removing all the head bolts and popping the head loose. Then I'll wait for the hoist and a helper to pull the head and fish the chain out while under tension.

I'm hoping I won't find anything upsetting, but with 383,000 miles, I'm kind of expecting some kind of surprise.

TheDon · #14 09-18-2012, 05:53 PM

Quote:

Originally Posted by 79Mercy

You'll prolly need a engine hoist to lift the head off the block, its gonna be stuck. I used a engine hoist when i did my M110 head and it made life so much easier.

Also here is another tip for re-installation that i didnt think about in the PM.

I took 5 or 6 of the old head bolts and used air tool to cut the heads off the bolts. I also cut slots in the top for a screwdriver. I screwed them into the block and used them as guides when i went to lower the head back down on the block. Those were a HUGE help.

I've used regular ole #2 pencils with the eraser end removed. Less likely to nick the head and do damage.