Installing new head on 602, help please..
 

So I got the old head off and am ready to install the new one. I have a few questions:

1)I'd like to to clean up the head bolt holes w/ a bottom tap, what is the thread size of the head bolts? I can measure If I have to, but hopefully someone who already knows can save me the time.

2) Is it necessary to refill the timing chain tensioner with oil, or can I just re install?

3)Since the I'm installing a remanufactured head, it's completely "dry." My plan is to blow out the head, soak my tappets in oil for a few days, and oil the cam bearing surfaces. Does this sound right, or is it necessary to pre-oil other parts of the head?

4)Can I just reinstall my old cam bearing caps, on my new head? Or is the procedure more involved?

Thanks in advance!

2) Immerse the tensioner business end down in light oil and and pump until resistance stops building. There's a formal procedure in the FSM that states what grade oil to use and possibly how many strokes.

3) There's a plug on the aft end of the head. Remove the plug and blow into the port to clean the lifter oil journals. I don't think soaking the lifters in oil will prime them but they'll be nice and oily when you install them. Definitely oil the cam bearing surfaces. Early FSMs say to remove the lifters with a magnet. Later FSMs say to use a non-magnetic tool such as a valve lapping suction cup. You don't want to magnetize the lifters so they don't retain ferrous flotsam in the oil.

4) Ideally the head and cam towers are a matched set. If not, you might get some peace of mind from using Plastigage to be sure the resulting cam bearings are within spec. Apply a strip to the head and tower halves of the bearings to be sure. Or torque the cam towers with the lifters out and convince yourself by feel that the cam spins freely and there isn't excessive clearance.

You know that MBUSA allows US residents access to the FSM online with a no cost subscription, right?

Sixto
87 300D^2

Yes, I have the manual. However, it is kind of skinny on details, at least for an amateur like me. :)

Thanks for the tip about installing the cam sans lifters to check fit ...so what would constitute excessive clearance?

"New" Head
 

'Not the Lifters or the Tensioner.
BUT I'd lube Everything Else up with Lubri (Liqui) Moly's Assembly lube just before final assembly.

Liqui Moly LM48 Montagepaste Assembly Lube Germany | eBay

Also,There IS a very specific sequence for torquing down the Cam Towers.
If not followed Can result in a cracked Cam.(Also,removal sequence)

Startekinfo has the FSM online and you should follow it.

Ask,Ask,Ask !

If I were slapping on a "New" head:
1.Check the Timing chain AND SPROCKETS ! also guides for wear.
(In case new ones needed)
2.Check the Oil Pump Chain ,Sprockets and Tensioner (Spring) for wear.
(Crazy me I would NOW,if offered the opportunity,LOCTITE the Oil Pump
drive Chain Sprocket BOLT into the O.P.)

GSXR has Print and Pictorials:
W124 Performance

Index of /images/OM602_head

This is the OM603 sequence most of which applies to the OM602:
Index of /images/OM603_head_replacement

124 Zone
 

You'll also find Ps2cho's "Website" VERY HELPFUL,especially the Third item on
the "Navigation" bar on the Left hand side of the home page.
(You'll be required to register for access)

LINK:
- News

Thanks for the links!

I'm not actually assembling the head itself(If that's what you mean),
it's a reman. from Metric Motors, that's already assembled except for the lifters. I suspect they used assembly lube when they put it together. I'm gonna give them a call to see what they recommend.

I'm replacing the vacuum pump, coolant pump, thermostat, injector nozzles and some other things I'm forgetting.

I decided to leave the timing chain for another day though, as this project is already taking too long given the limited time I have to work on it. The car has 180k miles and I checked the chain stretch via timing mark method; it's less than a degree off. The cam sprocket looks O.K.