Build Off to a Good Start. My '74 40 Series

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majdomo said:
Ok. So it's getting pressure and circulating at least past the pressure sender, but not through the rocker arm. Only thought I have there is pulling the rocker assemby and dizzy, checking all the passages in the rocker shaft, tower, and arms for blockages and running the oil pump with a drill to see if you get oil up through the bore in the head. Which is super involved, maybe others on here have a better way to diagnose...
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After removing the distributor, when I run the oil pump with a drill, will that do anything to throw off the timing when I put the distributor back on?
I plan to mark (and take picture) where the distributor is pointed before I remove it, so I make sure to put it back the way it was. TIA.
 
Yes, mark the base of the distributor to the blk, and mark where the rotor is pointing. Then you'll just have to line up the oil pump. I'd check the timing after, but you should be really close.
 
pb4ugo said:
Yes, mark the base of the distributor to the blk, and mark where the rotor is pointing. Then you'll just have to line up the oil pump. I'd check the timing after, but you should be really close.
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Agreed on this. Good luck!
 
As added info, the distributor “gear” is on the cam and higher than the oil pump shaft/stem and won’t turn/change when you spin the oil pump (it is fixed on the cam and only turns with the engine/crank shaft).
That said, once you spin the oil pump it will not line up with the bottom tang on the distributor. You either need to turn the oil pump shaft to line up with the distributor manually OR put the distributor in where you marked and hold it pushing down lightly while having someone turn the engine over with starter ( or rig up a wire / switch to turn over yourself).
 
I would pull the spark plugs and bring engine to TDC on compression for #1. Your rotor bug should be pointing at #4 spark plug hole. Lay a straight edge across the top of the center line of rotor and mark the position on the block and the dizzy housing. Now pull the dizzy and prime the oil pump. Install the dizzy using your alignment marks. Press down on the dizzy, rotate the engine - you will feel the dizzy shaft drop into the oil pump notch. Tighten the dizzy clamp. Crank the engine over until you see oil pressure on the gauge. Put in plugs.

Often for engines that have set for a long time. I have just pulled the plugs and cranked the engine over until I see oil pressure on the gauge. I also give each cylinder a spoon full of marvel's mystery oil - whirl the engine over to distribute the oil before, install the plugs before long term storage.
 
So, Im not getting any oil up through the head. After running the drill slowly, I could feel the resistance building up like if its building pressure.

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Are you spinning it in the correct direction? 600 is idle rpm 1200 is normal which is 600 rpm on the dizzy shaft and full speed in low gear on the drill motor.

Bad oil pump, blown/stuck open bypass at the oil pressure regulator, plugged passage or the oil pickup screen, bad gauge.
 
charliemeyer007 said:
Are you spinning it in the correct direction? 600 is idle rpm 1200 is normal which is 600 rpm on the dizzy shaft and full speed in low gear on the drill motor.

Bad oil pump, blown/stuck open bypass at the oil pressure regulator, plugged passage or the oil pickup screen, bad gauge.
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I was spinning it clockwise. I started slow with the drill, progressively speeding up to full rpm on the drill.
 
Those studs are fine, tho I would thread chase them. New ones shouldn't be too expensive. They are shanked not grooved.
 
Odds are the head gasket was installed backwards. It happens.

Which brings me back to the unanswered question of how that was not noticed by the shop you said adjusted the valves?
 
Oh man. This just got interesting. Well, I'll order a new head gasket and go from there.
If that's the case, there's no telling how long its been that way, the PO said he had it rebuilt years ago and hadn't done anything to it since. Could I have damaged the oil pump?
 
I'm not reading 233 old posts to figure out what is going on, post a short refresh. I doubt you damaged an oil pump by hand.
 
TwelveGravity said:
Oh man. This just got interesting. Well, I'll order a new head gasket and go from there.
If that's the case, there's no telling how long its been that way, the PO said he had it rebuilt years ago and hadn't done anything to it since. Could I have damaged the oil pump?
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No, the odds are that you will need another rocker assembly.

Why are you avoiding answering my question about the previous valve adjustment you told me about face to face a week ago?
 
My apologies Mark, I didn't recognize that you were asking me a question. Referring back to your question in post #213,
"What I don’t understand is how that could have gone unnoticed since you said that the valves had recently been adjusted by a well known shop in Stockton". I can't speak to why someone may not have noticed the lack of oil during a valve adjustment.
 
charliemeyer007 said:
I'm not reading 233 old posts to figure out what is going on, post a short refresh. I doubt you damaged an oil pump by hand.
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Thank you @charliemeyer007 in short, I recently started hearing a "Squeak" that resembled the noise of a throw out bearing but the noise would not come or go depending if the clutch was pressed in or not. At the Swap Meet last weekend here in Bakersfield, a few others were helping me listen to see if we could locate the squeak. During that, it was suggested that I do a valve adjustment. Later that weekend after adjusting the valves I ran the motor with the valve cover off to see if I could hear if that was where the noise was coming from, in doing so, I recognized the lack of oil coming up through the rocker assembly. That is when I posted asking what steps I should take to diagnose where the restriction was.
 
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The engine would seize up in short order without oil pressure so I doubt it ran very long without oil pressure.
So perhaps for example the pump recently failed, the oil pick up came loose or the screen clogged, the oil passage clogged or the pressure regulator failed.

I think that's a Mercedes-Benz hammer!
 
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65swb45 said:
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This is, in fact, the correct way to repair a BMW, speaking from first-hand experience.

Man that sucks. I was going to venture "head gasket" but didn't want to jinx it. Before tearing into the head, and I don't know if this works, but see if you can put a rod slightly longer than the length of the head down that bore. If the HG is backwards, it'll rest right on the HG. If not, it'll extend further than the height of the head and then you can continue diagnosing.

Or you could be super ghetto and punch a hole in it? But I won't suggest that.
 
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