3.5L M30 engine

i have compared it with the in car's headers , but it's difficult to measure….. that's why we call them spaghetti's :)
but think it will work…. also playing with the engine supports ( rotating the engine a bit clockwise with shims ) can do wonders.
 
took some time to get a new 2.2 kW starter motor as used in 850's. Installed /fresh oil /filter and we could test ….

- oil pressure comes on direct... as normal
- all cilinders almost 14 bar , except #3 with a good 13 . So also very good i assume for a engine from '86.

i think i can leave the engine as is for a spare and eventually install it that way ? I see no reasons to open up anything.

Yes, perhaps i can do the mod on the oil spray bar after cleaning it and mount safety washers on the bolts.


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yes, we do have a oil leak around the oil "reservoir" at the chain tensioner. It's dripping oil …. now that it's filled after starting the engine.
So that means pulling the balancer and the front covers.
Time to look for a complete gasket set.
As the front cover is part of the pan gasket i assume it's best to renew that also, and using some sealant on the exposed head gasket .
 
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That leak is very common but it is usually where the upper timing cover meets the block and lower cover. There needs to be sealant in the small recess where they meet against the head and block, you can do this by just removing the upper cover.
 
thanks Chris for info.... but it does leak for hours after starting ( = filling that reservoir) . So i assume the problem is in the lower cover gasket around/under the chain tensioner ?
 
Chris, plug doesn't leak…. i tested it today without the upper cover … and is keeps coming wet and dripping under the "reservoir". So i will need new gaskets on the lower cover also. Gasket must have been dryed out during years in storage …. as i see the ones on the upper cover : stone hard.

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If lower cover is leaking it will run down the block, it can’t drip below the tensioner reservoir. Right below the dowel there is a space for sealant to be used. If motor is out of car, I see the harmonic balancer is off, then pretty easy to do lower cover.
 
there was no sealant in the corners …. OEM ?
Not that it is important Chris , but it does drip below the tensioner reservoir. Some oil runs down the block with time but most is dripping . :)

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Hi Barry, I have a similar minor but annoying leak. So far I have made it much better by refitting only the upper timing chain cover with new gaskets and sealant (Hylomar blue) blobs in the 2 corners where it meets the CH gasket.

Much better, but not fixed. When I get to it (which may be a long long while!), I plan to take the upper timing cover off again and then carefully cut off the part of the CH gasket above the lower cover, flush with the front of the head/block. Then fix this gasket bit with sealant underneath and around the edges, and refit. (My guess is that oil is seeping under the CH gasket where it meets the lower timing cover.)
 
not in mine Drew , as you can see in the pic above , i kept the oil level beneath the CH gasket . So it is sure the lower cover gasket.
I even got all the bolts out , WD40 and replaced them to be sure there is good clamping force . Didn't help.
Now i need the ST for the "jesus" bolt :D

o well , it's best to renew also the front seal ( and rear ) now the engine is on a stand.
 
damned, that "Jesus" bolt was torqued and grown on the crankshaft. Even with a ST backup my wrench extension was just bending. I got it loose with the impact wrench keeping shooting.
 
You mean with the old style distributor? I'm not sure when they started with the newer style distributor on M30s, after -81?
That might very well be the case. I bought an -82 stamped head and moved over all components from my early -71 head.

Robert , did you also noticed the front bolt is no more in the center with the new style distributor, so doesn't match with the "new" style valve cover.
Due the big oil seal of course.

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Barry, I had this issue with my b35 motor as I kept the early style distributor and upper cover. I found another valve cover without the additional mounting bosses and studs but with rear oil filler location that worked.
 
Robert , did you also noticed the front bolt is no more in the center with the new style distributor, so doesn't match with the "new" style valve cover.
Due the big oil seal of course.

No, I just moved over all old parts to the new head core, this picture shows all that I replaced, except the cam which is a CSi 272°.
-82 head core (actually stamped -81), valves, springs, retainers.
All other parts including the cam, I moved over from the old -73 head, and I didn't run into any problems:)
But it's good to know that the newer valve cover wont fit with the old style distributor, I didn't know that.


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so in my search for valve cover / delco and front cover i found this '76 M30B30 and bought it at a bargain price.
Not only the valve cover front bolt doesn't match , the front cover is more inward on a B35 , so that with a old style front cover the gasket/valve cover gasket surface only match half of the gasket surface from the front cover.
One needs them in pair , valve and front cover. ( and of course gasket )

Must see what condition this engine is ... only a positive surprize would it be "good" …. exterior is nice….:)
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edit… first time i see Zenith carbs…. OMG...with all that magic vacuum … and 100 commands… not for me :D The Webers 32/36 on my blue coupe are 10 times more simple…. and work as well. That needless complex gas factory is for the scrap bin. :eek:
 
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yep, water in the oil.. a lot :( so , surprize, but a bad one :D probably demounted with gasket or crack in head…. ok, a coming winter fun job opening it for inspection…
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i should check but afraid it's water.... when i drained it the first flow was clear "water", afterwords the brown oil . It could have been long time stored that way...
 
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