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Offline aboyandhisdog

No oil pressure
« on: March 19, 2020, 02:48:15 PM »
I just installed a newly rebuilt L134.  It's all hooked up and ready to go.  I put about a quart into the oil gauge port in the block with an old transfer pump I had but am unable to fill my spin-on bypass filter.  Filled crankcase also. 

Cranked engine and it fired right up.  But about 20 sec. in, I noticed no oil pressure on the gauge.  Shut her down right away.  Pulled the brand new pump out and packed it full of assembly lube.  Removed the plugs so I could spin the engine with the starter only.  Cranked several times for 20 sec. each and still no pressure. 

I decided to put my old, (known to be good) pump on.  Filled it with assy. lube also.  Cranked starter again and still no movement on the pressure gauge.  I also verified that there is no flow to the oil filter.

Feeling very defeated right now.  But I have a few questions: 

1)  How long should it take oil pressure to build in a "new" engine? 
2)  Would my filter need to fill before pressure comes up?  (I doubt this as we do filter changes all the time without issues)
3)  How much turning of the engine with the starter is acceptable if there is a chance the oil isn't flowing?
4)  What am I over-looking?  What should I try now?

This engine is working my last nerve.  I've had to heli-coil 8 head studs that have failed after working fine previously.  Five ruined head gaskets!  The oil pump had been indexed wrong so I had to correct that.  A number of other things.  But it is this oil pressure situation that has me confounded the most.

As ever, thank you for your insights!

Offline athawk11

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Re: No oil pressure
« Reply #1 on: March 19, 2020, 04:30:50 PM »
I've never tried this, but in theory it should work to tell you if your oil pump is circulating oil.

Disable the engine from actually starting.  Disconnect the oil gauge line, drop the end into a container, then crank the engine.  If oil shoots out, your pump is pumping.  It may take a little time to flow if your oil filter isn't filled up yet.

Each starter has its own tolerance to over cranking.  I've killed an MZ4113 6v starter installed in a 12v system after on-and-off consistent cranking for about a half hour.  I have one of the modern high torque starters on Rachel's 3A...and I doubt I could ever kill that off.
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Offline aboyandhisdog

Re: No oil pressure
« Reply #2 on: March 19, 2020, 05:28:07 PM »
Thanks, Tim.  I have the same starter as Rachel, but it isn't the starter I'm worried about.  I don't want to damage my engine by cranking it without a good oil supply. 

As for testing the flow, I disconnected the oil supply line at the filter (the one that comes up from the block) and I didn't get a drop out of it while cranking.  I have an appointment next week with my mechanic who has a pre-oiler and a lot of knowledge.  I was hoping to solve this before then, but I really don't want to do any harm to my engine.  I'm not too proud to call in the big guns when I need to but this sure has been demoralizing!

Offline SteveKfl

Re: No oil pressure
« Reply #3 on: March 19, 2020, 07:23:40 PM »
Have you tried taking the spark plugs out to free spin the engine faster without suction on the intake?  I would drop a little "Mystery Oil" in the cylinders to lubricate the pistons and walls while cranking.  Does the filter container have any oil to lubricate the chain area?  Have you tried disconnecting the lines from the filter to see if oil flows down them freely?  Again I would use Mystery Oil penetrant which flows easier for testing without pressure.  Maybe add a little pressurized air to force it thru.  If you're not familiar with the product, it actually can be used as a "top oil in your gas" or "oil additive" as well.  It won't hurt anything.  My dad used it back in the 50s and I still do.  I'm just suggesting things to verify "easy to see" items before the expensive mechanic asks you "about them" or spends time testing them.  Realistically, the broken pump's "driven gear" concerns me about the "drive gear" condition, but let's hope that's not the case.  Good Luck!
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Offline aboyandhisdog

Re: No oil pressure
« Reply #4 on: March 19, 2020, 09:21:36 PM »
I just read this thread on the 2A and he has an almost identical issue as me.    However, his is an F-head (mine an L-head), not too sure of all the differences or what they have in common. 

Well, I'll take it to my mechanic on Wed. and see what he thinks.  Thanks BW for mentioning the 2A thread. 

BTW, my thread on Pre-oiling the engine kind of took a turn to someone else's project which is why I started this very similar thread.  No problem, but I just don't want everybody to be confused as to why I started this thread.  Steve, I think your comment about the "broken pump" is in regards to Tow Hook's issues on my "Pre-oiler" thread.  I don't have a broken pump or drive gear.

Everybody nice and confused yet?

Offline Rus Curtis

Re: No oil pressure
« Reply #5 on: March 19, 2020, 09:40:11 PM »
I also posted on the other thread but it applies here too.  Some obvious things could be checked to help eliminate a few things.

Weird how all these oil pressure issues are happening.
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Offline SteveKfl

Re: No oil pressure
« Reply #6 on: March 20, 2020, 10:57:23 AM »
Sorry "Tom", for my confusion and tom-foolery.  lol  I guess I broke down "under the pressure" and just looked at "topic title" when I came back to reply, and did not look back into the thread for content or author.  My bad!  Haste makes waste.  In either case, the "solutions" should prove to be informing.  Good Luck to both!
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Offline aboyandhisdog

Re: No oil pressure
« Reply #7 on: March 27, 2020, 02:20:58 PM »
The "no oil pressure" mystery has been solved.  The engine builder did, in fact, leave out one galley plug.  Fortunately no dire consequences apparent, as she is purring like a kitten.  Supposed to warm up in a day or two so I can get it out on the road for the maiden voyage.  Thanks to everybody who helped with this.