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Author Topic: No oil pressure on a new engine start up. Help please  (Read 403 times)

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No oil pressure on a new engine start up. Help please
« on: December 02, 2018, 03:31:41 pm »
Okay, I did a quick search and didn't find any pertinent results. My problem at the moment is I'm at the point of doing my initial start up of my 72mm bore dragbike engine. For some unknown reason, I am unable to get oil up to the oil alley. Yes, I did properly prime the oil pump before bolting it on the engine.  I even pre-lubed the engine with a makeshift pressurized luber so I know oil is going to the top end and the mains and rod bearings. I'm simply not getting oil from the pump to the galley wen spinning the engine over.

Help with questions please. I'm not going to put fire in the hole until I know I have oil pressure. Thank

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Re: No oil pressure on a new engine start up. Help please
« Reply #1 on: December 02, 2018, 04:22:39 pm »
I think I'm goinq to remove the oil filter and introduce oil both ways in the passages. I made a pre oiler out of a garden sprayer and added an air fitting to pressurize it easier. 

Offline Tracksnblades1

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Re: No oil pressure on a new engine start up. Help please
« Reply #2 on: December 02, 2018, 05:15:53 pm »
That's pretty innovative.. How much pressure can you pump it up to..?
If you were closer I have a DIY stainless steel pressure bleeder primer that pops off @ 60 psig.
Is your oil filter bolt/bypass oem...?  Or the aftermarket one that other members have had trouble with...?
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Re: No oil pressure on a new engine start up. Help please
« Reply #3 on: December 02, 2018, 05:32:40 pm »
Decided to remove the filter and pressurize the galley through the oil filter bolt hole opening. I immediately had oil flow out of the pressure gauge adapter on the side of the engine. I'm now going to put the pressure gauge back on and let oil go to the top end to be sure the stud oil path is clear as well. I'll spin the engine over a few times to lubricate the cam and mains again. Hopefully oil will also come out of the entry hole for the filter housing.

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Re: No oil pressure on a new engine start up. Help please
« Reply #4 on: December 02, 2018, 05:39:16 pm »
Uncertain about the limits of the plastic container but I have my compressor outlet pressure reduced to 40 psi. That's more than enough to get oil moving unless there's a serious obstruction. I know if you manually pump this thing up to much, the rubber seal at the screw in part of the pump will blow out. It hasn't happened yet in my testing. You also have the option of pressurizing the sprayer by hand. I needed to install a ball valve on the outlet side of the sprayer but got in a hurry at tractor supply and forgot to get the parts.

That's pretty innovative.. How much pressure can you pump it up to..?
If you were closer I have a DIY stainless steel pressure bleeder primer that pops off @ 60 psig.
Is your oil filter bolt/bypass oem...?  Or the aftermarket one that other members have had trouble with...?

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Re: No oil pressure on a new engine start up. Help please
« Reply #5 on: December 02, 2018, 05:42:21 pm »
I got the filter bolt off an engine at the local junk yard. I really don't know if its OEM or not. Seemed stock appearing to me. If oil flows from the pump to the inlet of the filter housing when i crank it over, I'll know it could be a problem with the bolt not allowing oil to pass through into the engine.

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Re: No oil pressure on a new engine start up. Help please
« Reply #6 on: December 02, 2018, 06:14:51 pm »
Has anyone ever tried to draw a vacuum from the inlet hole at the oil filter housing?? If there's air trapped inside the pump or the oil lines leading into the engine, it seems this method would evacuate it out. I need to find a rubber plug of some sort to fit snuggly inside the hole and drill into the plug with a fitting so I can attach the vacuum pump inlet line.

I did replace the oil pump with another from a known, running engine so I really don't think its the pump but anything is possible.

I spun the engine over just now but got no oil coming into the filter housing from the pump. I used a pump oil can to push oil through the opening towards the pump but still nothing came out. Dang it. Frustrated with this thing now but its got my time, and my money so I've got to work through this process until its solved. It appears the oil tank is still full so the pump may not be pulling oil out. Odd, I primed the pump and got oil flow before I installed it on the engine. I'm going to pull the incoming oil line fitting off now to see if anything gravity flows out.

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: No oil pressure on a new engine start up. Help please
« Reply #7 on: December 02, 2018, 06:33:37 pm »
Frank, fire her up and see if the pressure pops right away?! Shut her down within a few seconds if not. You'll' be OK.   
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Re: No oil pressure on a new engine start up. Help please
« Reply #8 on: December 02, 2018, 07:32:20 pm »
Hmmm, I'll pass on that thought my friend. Its just my preference to see oil flowing prior to actually starting an engine up. Comes from my past days of playing with race cars.  I hope to figure something out soon or this one won't get to run any time in the near future.

Frank, fire her up and see if the pressure pops right away?! Shut her down within a few seconds if not. You'll' be OK.

Offline PeWe

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Re: No oil pressure on a new engine start up. Help please
« Reply #9 on: December 03, 2018, 01:02:00 am »
It should pump oil thru the oil galley (where prssure gauge can be installed) rather soon when using the starter.  I got overflow from this one after max 10-15 sec last time.
- Is the oil hose to case blocked or too long so it is pinched and cannot supply oil to pump?
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Re: No oil pressure on a new engine start up. Help please
« Reply #10 on: December 03, 2018, 06:20:40 am »
I did pull the inlet oil line off at the engine last night to verify flow. Its got stock lines and is not obstructed.

It should pump oil thru the oil galley (where prssure gauge can be installed) rather soon when using the starter.  I got overflow from this one after max 10-15 sec last time.
- Is the oil hose to case blocked or too long so it is pinched and cannot supply oil to pump?

Offline bwaller

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Re: No oil pressure on a new engine start up. Help please
« Reply #11 on: December 03, 2018, 03:45:44 pm »
You can add oil within the system but it cannot hold a "prime". If you used assembly lube or have things well oiled, give it a go.

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: No oil pressure on a new engine start up. Help please
« Reply #12 on: December 03, 2018, 04:03:57 pm »
You can add oil within the system but it cannot hold a "prime". If you used assembly lube or have things well oiled, give it a go.

I have had to do it this way a few times now myself which is why I suggested it. They popped pressure almost as soon as it fired. Would I assume you have an oil pressure gauge added?
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Offline MRieck

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Re: No oil pressure on a new engine start up. Help please
« Reply #13 on: December 03, 2018, 07:17:16 pm »
You can add oil within the system but it cannot hold a "prime". If you used assembly lube or have things well oiled, give it a go.
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Offline 754

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Re: No oil pressure on a new engine start up. Help please
« Reply #14 on: December 03, 2018, 07:28:11 pm »
My personal biggest worry.....is winding a motor to red line , that is not fully warm..
Letting your motor run for 15  or 20 seconds, after all the pre oilng you did, would not worry me..
 But taking down the strip not warmed enough.. that would worry me..
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Re: No oil pressure on a new engine start up. Help please
« Reply #15 on: December 03, 2018, 09:18:20 pm »
Yes, I do have a pressure gauge on the oil galley..

I'll probably cross my eyes and fire it up in the next day or so. I need to see what I have before all the dragstrips around here close for the remainder of the year. Still need to get the lockup clutch issue worked out but that won't affect a n/a pass.

You can add oil within the system but it cannot hold a "prime". If you used assembly lube or have things well oiled, give it a go.

I have had to do it this way a few times now myself which is why I suggested it. They popped pressure almost as soon as it fired. Would I assume you have an oil pressure gauge added?

Offline Tracksnblades1

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Re: No oil pressure on a new engine start up. Help please
« Reply #16 on: December 04, 2018, 03:12:42 pm »
Yes, I do have a pressure gauge on the oil galley..

I'll probably cross my eyes and fire it up in the next day or so. I need to see what I have before all the dragstrips around here close for the remainder of the year. Still need to get the lockup clutch issue worked out but that won't affect a n/a pass.

You can add oil within the system but it cannot hold a "prime". If you used assembly lube or have things well oiled, give it a go.

I have had to do it this way a few times now myself which is why I suggested it. They popped pressure almost as soon as it fired. Would I assume you have an oil pressure gauge added?

Success.....?????
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Re: No oil pressure on a new engine start up. Help please
« Reply #17 on: December 04, 2018, 03:27:36 pm »
Haven't attempted anything yet. Forgot I had an employee Christmas dinner to attend yesterday so I haven't made it to the shop. Going tonight in a few

Yes, I do have a pressure gauge on the oil galley..

I'll probably cross my eyes and fire it up in the next day or so. I need to see what I have before all the dragstrips around here close for the remainder of the year. Still need to get the lockup clutch issue worked out but that won't affect a n/a pass.

You can add oil within the system but it cannot hold a "prime". If you used assembly lube or have things well oiled, give it a go.

I have had to do it this way a few times now myself which is why I suggested it. They popped pressure almost as soon as it fired. Would I assume you have an oil pressure gauge added?

Success.....?????

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Re: No oil pressure on a new engine start up. Help please
« Reply #18 on: December 06, 2018, 06:07:23 am »
Frank: Go slow as a missed oiled motor can cost you dollars and time !!!! The fire trucks we drove for 30 years had PRIMIMG PUMPS TO PURGE AIR IN THE SYSTEM and to run that pump up into high RPM'S WITH NO WATER  [ 1000 gallon water tank ] and the bronzed fingers on the pump would buried up and locked the pump up rather quick...... hydraulics.  I went to every pump school they had and but I drove the 100' Hook and Ladder better safe than sorry.

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Re: No oil pressure on a new engine start up. Help please
« Reply #19 on: December 13, 2018, 12:18:00 pm »
Aaaand?
1971 Honda CB750 Four K1 [Engine: CB750E-1113521 / Frame: CB750-1113838]
1977 Seeley Honda CB750F (F1) [Engine: CB750E-2551214 / Frame No: SH7-655F]

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Offline Remcod

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No oil pressure on a new engine start up. Help please
« Reply #20 on: December 13, 2018, 12:56:22 pm »
What worked for me was to first poor half a liter or so of oil down the tappet holes to get some oil in the sump for the pump to take in. Then hold the bike a bit sideways (i use the sidestand but you might not have it on a drag bike) and poor oil down the galley above the contactpoints, probably where you put the pressure gauge untill it takes no more. Put the plug back on and level the bike. Put some in the oiltank. Than run the starter engine with the killswitch off to not actually start the engine. Oil pressure must be there in 10-20 seconds. Mine did, it might work for you.

Reasoning behind is that you feed oil to the pump again from above forcing the air out.
« Last Edit: December 13, 2018, 01:06:59 pm by Remcod »

 

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