M30B35 swap questions...

sreams

sreams

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I've pulled my original 3.0 out and I am transferring parts to my 1991 M30B35. It will be carbureted (for now).

The first question is regarding the oil pump. I'll be using the old pan. I've moved the pump over from the 3.0 to the new engine and it fits just fine... but it appears the oil pump chain that is currently on the newer engine is not long enough. Is that expected?

The second question: I'd like to switch to the newer style cooling fan that threads on (reverse thread). The M30B35 water pump only has a single groove pulley. I'd like to move my old pulley over, but the mounting holes on the pulley don't match those on the pump. The center hole in the pulley also doesn't match the hub on the pump. Is there any way to do this? Or should I stick with the old style fan/pump?

Thanks ahead for any advice.

-Scott
 
Swap

Watch out for the oil filter housing....the 35 block needs a plug if you use the M30 part. Discussed before and not intuitive. zero oil pressure otherwise....not good.
 
In terms of the oil pump, I don't remember having a problem with it. However, check the sprocket size for the old and new pumps; you may need to swap the B35 sprocket onto the E9 pump.
 
The normal course would have been to use the b35 pump with the earlier pickup.

IIRC, for E9, E3, E12, and early E24.

The early pick up is 1/2" shorter.
 
Early pumps used shims to account for chain tension- late pumps have no shims but use a tensioner. Later chains are usually stretched like crazy from the tensioner.
Early pumps have thicker bolt lands that can interference with the rod nuts on the two upper pump casing bolt heads.
Early engines are 80 mm stroke and later engines are 86 mm stroke thus creating the interference.
Early oil pumps have 3 bolts attaching the oil pump gear- later pumps have a single nut.

Use the newer pump with no shims with the old pick-up with the new tensioner with a new chain and verify you have no interference between the bolt and the nut on cylinder #1. There is no gasket needed. Either gear is fine.
If you have interference- You can cut the bolt land or grind the bolt head or the rod nut or any combination of those 3 things.
Always rotate the engine and examine closely- remember that heat makes things expand.
Make sure you torque the mains properly when you install the pick-up support bracket and spacers.
 
Early pumps have symmetrical bolt holes on them for the pulley.
Late pumps have rectangular bolt holes for the pulley.
Considering the radius of the newer pulleys and the effect of clocking the pump/alternator/ac compressor- you are better off using the later pulleys, dampener, and pump. Good news is that they all line up.
 
BTW-the early oil pump gear is a different size

Part of the clocking ist gut movement.
 
Thanks for all of the great help from everyone. I remember reading about having to plug that hole in the block where the oil filter housing goes... but I would have forgotten if it hadn't been mentioned here.

sfdon said:
Use the newer pump with no shims with the old pick-up with the new tensioner with a new chain and verify you have no interference between the bolt and the nut on cylinder #1.
Click to expand...

The M30B35 I picked up did not have an oil pump. Is there some problem with just using the older pump and pickup on the new engine? Or would that not work?

-Scott
 
I just counted twice... and it looks like the old M30 oil pump chain has 46 links, while the chain on the M30B35 has only 44 links. That would explain the difference. Parts websites also seem to show that the newer engines have two fewer chain links than the older ones. Using a new 46-link chain should solve my problem.

-Scott
 
If you use the complete old pump

Don't forget the bracket from the main bearing and re-torque to 60
Nm. And don't forget the old chain and gear. I prefer to use the new
style chain, tensioner, gear and pump with the old style pick-up.
I would think twice about using the big gear from the old pump
with the new tensioner- could be fine but you got to wonder why
they changed the gear size.
 
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