New Project! 87 300TD - Page 6 - PeachParts Mercedes-Benz Forum

87tdwagen · #76 10-05-2022, 02:54 PM

Good job!

I removed the upper bolts (red). The turbo will hang a little when those are removed and caused no interference when reinstalling the head in my case.

Eric4 · #77 10-05-2022, 05:12 PM

Next, I've got to prep the chain and sprocket for removal. Looking at the chain guide pins, one seems easy to pull with a bolt and washers, but the lower pin looks to be mangled, and I can't thread in a bolt. Is this how it's supposed to look? Or did the last person working on it, cause some damage?

Do I pull these out entirely? Or just far enough to remove the chain guide?

dieselbenz1 · #78 10-05-2022, 07:10 PM

Looks like someone had gotten it out a bit. Doesn't look like there is enough to grab onto. Are you able to retap the to 10 mm thread? Since it's out a bit it may come out easy. The pins are tapered so once released they come out easy and yes they need to be removed.

Eric4 · #79 10-06-2022, 11:51 AM

I'll snag up a 10mm (x1.0 or 1.5?) tap, and a small pair of vice grips, as there might be enough meat to grab onto with the vice. Planning to try tapping first however.

Good to know the pins are tapered. Hopefully this won't hold me up...

Should I look for a replacement pin as well?

87tdwagen · #80 10-06-2022, 01:30 PM

Use the bolt that threads into your other pins to get the right size tap, they are all the same. I'd plan on replacing at least that one buggered pin, if the others are fine reuse them

Eric4 · #81 10-06-2022, 03:05 PM

Got the bottom pin free! I bought a tap set, and the size was 6x1mm. Used a 11mm socket as a spacer, to pull the pin out. Slowly adding washers as the pin was pulling.

Once these pins are pulled, will the guide want to fall down into the block? I want to prepare for this if so.

I'm following the procedures from here:
https://w124performance.com/service/Index/MiscFiles/01-415.pdf

One thing I'm unsure of, is when to remove the sprocket vs camshaft? I'm guessing the head can be pulled with the cam still installed, and just the sprocket removed? When unbolting the sprocket, does anything need to be done to keep the engine from leaving TDC?

ah-kay · #82 10-06-2022, 05:11 PM

The chain guide is 6+" long. It wouldn't go anywhere.

Zip tie the timing chain to the sprocket to hold the timing. This is very important. There are head bolts under the cam tower. The cam can stay on but you need to remove the cam tower, remove the head bolt then put the cam tower back.

Eric4 · #83 10-09-2022, 05:51 PM

I'll have to remove the cam anyway, as it needs to be swapped onto the new head...First I need to unbolt the sprocket though, I'm guessing

The sprocket is zip tied securely, engine is TDC, but I still am struggling with the fuel heater pipe at the back of the head. The circlip has been pulled, and it seems to wiggle inside the mount. I have read that there's another attachment on the oil filter housing, but don't see anything. This piece looks fragile, and I don't want to break anything. Does the hex bolt that it's fitted into need to be loosened as well?

I am reading in the service manual, that the chain tensioner needs to be removed. Is this step required? Or will the sprocket fit onto the cam on the new head as is?

ah-kay · #84 10-09-2022, 06:51 PM

Fuel heater pipe removal: remove the circlip. Remove 2 hex bolts at the back of the filter body to loosen the heater pipe. Have you removed the inlet manifold and the hard lines? That would give you a better visual at the back of the head. The head can be lifted if the pipe is loose. You can't remove it completely without removing the water hoses.

The timing belt tensioner needs to come off. Just undo it but you need a big socket. There is a half moon shape spacer where the sprocket attached to the cam shaft. Don't loose it. Cam shaft, sprocket is the same for old or new head. But the prechamber is different if you bought a #22 head.

Good luck.

Eric4 · #85 10-10-2022, 03:15 PM

Quote:

Originally Posted by ah-kay

Fuel heater pipe removal: remove the circlip. Remove 2 hex bolts at the back of the filter body to loosen the heater pipe. Have you removed the inlet manifold and the hard lines? That would give you a better visual at the back of the head. The head can be lifted if the pipe is loose. You can't remove it completely without removing the water hoses.

The timing belt tensioner needs to come off. Just undo it but you need a big socket. There is a half moon shape spacer where the sprocket attached to the cam shaft. Don't loose it. Cam shaft, sprocket is the same for old or new head. But the prechamber is different if you bought a #22 head.

Good luck.

On the heater pipe, I've now removed the hoses, and it moves even more, but still is locked onto the head. There is a large nut between it and the head, does that have to be removed too?

Timing belt tensioner is removed, as well as the sprocket. Hopefully the picture below is referring to the half moon spacer, as I didn't see anything between the sprocket and camshaft when I pulled it off...

Eric4 · #86 10-10-2022, 04:21 PM

Cam is out, ready to unbolt head bolts

When do I remove bolts 'a' and 'b' in the sequence?

dieselbenz1 · #87 10-10-2022, 06:14 PM

First

Eric4 · #88 10-10-2022, 11:37 PM

The head is loose! I still don't have a hoist, but its broken free by hand. I may wrangle a second person on removing the old head, but I can already see the advantage of a hoist for the new head install. One thing I noticed on the head bolt removal, between CYL 2 and 3, the bolt was a bit corroded. Seems like that was a location of a crack or head gasket split with the compression test too...

What's the protocol on the gasket sealer? Is hylomar blue the standard? How much do you apply, and to both sides?

I snagged an OEM Mercedes Benz head gasket from Pelican Parts. I figure the added cost is worth the assurance.

Before installing the new head, should I blast the prechambers with brake cleaner, and do any other prep before install? I considered new valve seals, but didn't have the tools to remove them. The new head will get a fresh set of INA lifters.

barry12345 · #89 10-11-2022, 08:58 AM

I always inverted the head and put a little thin fluid around the valve heads.. Especially when getting it back from a machine shop. To check for valve sealing. Personally I would do the same on a used head.

In the day head work was so cheap a used head usually got a valve job. Like a lot of other things today. Cheap is ancient history.

I might do it on a flat head like these. By putting some fluid into the intake and exhaust runners with the head upright. Yet elevated off the surface A small mirror could be used for inspection if needed. Although inverted is good enough.

87tdwagen · #90 10-11-2022, 10:11 AM

Head gasket sealer is not required, but if you have the Hylomar, the extra sealing assurance is well worth it. Use a light coating on both sides.