om603 head removal and recommend head shop - PeachParts Mercedes-Benz Forum

natew · #1 01-14-2014, 01:01 PM

I have removed everything from the head from my donor motor. Looks like the last things I have to do is pull the retaining pins and unbolt the head from the block. In the benz manual I did not see anything about removing the timing chain, loosening the tensioner or removing the cam or cam gear. What is needed to remove the head from the block in terms of timing chain? The manual just states remove the 2 bolts under the valve cover at the front of the head. I don't see how that can release tension from the chain.

What size bolts and washers can I use in place of the special benz tool to pull the pins?

Does anyone know the size of the special socket to remove the head bolts?

Is there a recommended good shop in southern california that is familliar with Mercedes diesels that can inspect, clean, and machine the head and install valve seals, lifters, and any other parts it may need? I really want to come in under $500 for labor.

I don't want to bend open valves while transporting head to the shop. Is there a good way to protect/package it for transportation? Lay it upside down resting on the cam on some cardboard?

sixto · #2 01-14-2014, 02:42 PM

Get all the manual sections you need at www.startekinfo.com . Check the top of each section for related sections, pre-work, adjustments, etc. Don't attempt this job based on internet DIYs.

You can remove the head around the loose chain but not around the sprocket on the cam. Set the engine to TDC, mark the chain on the sprocket, remove the tensioner, remove the sprocket, let the chain drop into the engine, lift the head. Besides the 2 bolts into the front cover, there are 2 bolts by the big fuel filter that hold the head to the block.

Any of the countless bolts in the car that take a 10mm wrench will thread into the guide rail pins. I think they're M4-1. Take one to Home Depot and use the thread gauge in the nuts and bolts aisle to be sure, or find a named nut that fits. Get the highest strength bolt they have. An inch long bolt should do it. Get washers that won't bend. I use used injector seals. Use something like a socket over the upper pin which sticks out of the head to serve as the pivot for the belt tensioner upper perch. Add washers as the bolt bottoms in the pin. The bolt will break in the pin if you keep tightening.

I don't remember the size of the XZN/triple square/double hex bit for the head bolts. It's either 8mm or 10mm. I use a set like his from the auto parts store - Lisle 60750 12 Point Triple Square Bit Set : Amazon.com : Automotive - which has what I need without thinking about it. The cam has to come off since these short bits won't go through the cam towers to the hidden head bolts. Otherwise you need much longer bit. Get the special tool shown in the manual or use a thin rod or screwdriver to measure how long the bit has to be.

If you leave the cam installed, fabricate a handling and transport cradle. Drill holes in strips of wood, 2x2 should do it, the length of the head so you can bolt the wood to the head. Position the wood to clear open valves.

Sixto
87 300D

natew · #3 01-14-2014, 03:05 PM

Does the engine HAVE to be at tdc to pull the head? Since I'm having work done to the head it doesn't really matter the chain to sprocket mark because I'm going to have to redo the timing when the head gets back from the shop anyway right? I know installing tdc matters but removing too?

Thanks a lot for all the help you've given me so far!

sixto · #4 01-14-2014, 03:17 PM

It's so much easier to turn the crank and IP to TDC with the cam in place. It's clumsy to turn the crank and keep the IP in time with the head off. This sounds like your first time working on this engine. You don't need more variables.

Sixto
87 300D

whunter · #5 01-14-2014, 03:18 PM

Quote:

Originally Posted by natew

Does the engine HAVE to be at tdc to pull the head? Since I'm having work done to the head it doesn't really matter the chain to sprocket mark because I'm going to have to redo the timing when the head gets back from the shop anyway right? I know installing tdc matters but removing too?

Thanks a lot for all the help you've given me so far!

Check your G-mail.

.

natew · #6 01-14-2014, 03:21 PM

Ok I will do that. This is my first time ever pulling a head on any car and first time major engine work on a diesel. I've had a w210 for about 3 years and have done everything it's needed except rear main. I had a shop do that one.

natew · #7 01-15-2014, 12:06 AM

How do you think I can remove this? It's split all the way to the bottom of the threads. I got the other pin out no problem.

sixto · #8 01-15-2014, 12:13 AM

One option is to grab it as tight as you can with vice grips then hammer on the vice grips. Don't try to spin the pin.

How did that happen?

Sixto
87 300D

ah-kay · #9 01-15-2014, 12:19 AM

Is this the top one? I butchered up the top one. I drilled a small hole at the back and punched it out. It is a piece of cake. I filled the small hole with RTV but it is not really necessary.

natew · #10 01-15-2014, 12:51 AM

Ya the top one. I got vise grips and kept spinning it until loose. Then pulled as hard as I could while spinning it. Broke off once but I got it out.

It was siezed in there all rusty. I even sprayed copious amounts of pb blaster before attempting to pull them. I also didn't loosen the tensioner before attempting the top and that may have contributed.

natew · #11 01-15-2014, 11:06 PM

So I got down to head bolt #7 and the bolt head stripped out. What can I use to get it out?

Obamalamadingdong · #12 01-16-2014, 12:39 AM

I just posted a nice FSM Diesel Engines 602, 603 in the Parts For Sale forum if you decide you want or need a paper manual! Good luck on this project !

whunter · #13 01-16-2014, 01:28 AM

Quote:

Originally Posted by natew

So I got down to head bolt #7 and the bolt head stripped out. What can I use to get it out?

Drill the bolt head, and pop the top of it off.

.

natew · #14 01-17-2014, 08:10 PM

Drilled with 1/4 then 5/16 then hammered a t50 in there and it came out. Thank you everyone! I don't see any cracks or burned valves. Off to the shop for a valve job and then I'll probably be back for help putting it back together.

natew · #15 01-20-2014, 08:44 PM

Today I pulled the head off the engine in the car. I had it at tdc(piston 1 is at the top). On the cam the timing mark was pointing down at the bottom instead of pointing up. Isn't the cam timing mark supposed to be at the top?