Oil Pump issues- opinion needed

B

Bruce_MO

Well-known member
I finished a car a few months ago with a touring engine from Antique Engine Rebuilding...inserts, counterbalanced crank, etc. I rebuilt the oil pump with a kit from Bratton's and have been running it lightly for about 20 miles. I noticed that the tappets were a bit noisy at start-up and after a few minutes they quieted down. That worried me. I had pulled the lower end of the oil return pipe after start-up and got some oil flow after what seemed to be a long time. To confirm things, I took an old oil return pipe and cut a section out of it and put some clear 3/4" ID plastic tubing in place, and then started the engine up. It took 2 minutes to get oil to show in the tube. I then put the tube on my other "A" with very many miles on it, and I had oil in 30 seconds after sitting for weeks w/o running. So I'm in the process of replacing the pump.

Questions:
1) Are all the pumps available from vendors "equal" or is there a preferred vendor? DOes Melling make a pump for A's?
2) Whats the likelihood that I did significant damage?
3) Should I pull a main or rod cap and inspect, or should I just put in the new pump and drive it?

Thanks for your opinions.
 
Don't expect much oil flow, if any at all, through the oil return pipe when sitting level. That is NOT it's purpose. When level or downhill, oil flows over the front dam, past the timing gear, and fills the all-important dipper tray. A long uphill run would starve the dipper tray front feed as the valve chamber fills. The oil return pipe only serves to provide oil flow to the front of the dipper tray while going uphill. If the oil return pipe drained the valve chamber before it overflowed the front dam, the timing gear would get no oil. THAT would be a problem.

A valve chamber that fills fast may have blocked or restricted passages to the bearings. The fact that your new rebuild takes longer to fill than an old engine is not necessarily a sign of a problem. If you want to see if your pump works, take off the valve cover and observe the outlet at the front of the chamber as you crank the engine. If the front dam height on the old engine is higher than the new engine that will account for your observed differences, too.
 
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I would nstall the new one and perform the same test. If it pans out good run it gently and check for noise. No noise? keep going. The car are pretty forgiving and if you read all the posts covering engine that seem to run fin with blocked oil pump screens..........well you get the idea.
The pump has to move a lot of oil to the valve gallery to get return oil back.
 
why not contact the rebuilder and have him look at it? maybe save you the headache! That's what I did and got my problems fixed without a cost. Most engine rebuilder I know stand behind their work!
 
bogdonj said:
why not contact the rebuilder and have him look at it? maybe save you the headache! That's what I did and got my problems fixed without a cost. Most engine rebuilder I know stand behind their work!
Click to expand...
Excellent advice! Once you pull the pan, any warranty expressed or otherwise, will be voided.
 
Bruce_MO said:
I finished a car a few months ago with a touring engine from Antique Engine Rebuilding...inserts, counterbalanced crank, etc. I rebuilt the oil pump with a kit from Bratton's and have been running it lightly for about 20 miles. I noticed that the tappets were a bit noisy at start-up and after a few minutes they quieted down. That worried me. I had pulled the lower end of the oil return pipe after start-up and got some oil flow after what seemed to be a long time. To confirm things, I took an old oil return pipe and cut a section out of it and put some clear 3/4" ID plastic tubing in place, and then started the engine up. It took 2 minutes to get oil to show in the tube. I then put the tube on my other "A" with very many miles on it, and I had oil in 30 seconds after sitting for weeks w/o running. So I'm in the process of replacing the pump.

Questions:
1) Are all the pumps available from vendors "equal" or is there a preferred vendor? DOes Melling make a pump for A's?
2) Whats the likelihood that I did significant damage?
3) Should I pull a main or rod cap and inspect, or should I just put in the new pump and drive it?

Thanks for your opinions.
Click to expand...

You did not say if you are running pressure to the mains and rods. That would make a difference. You say you rebuilt the pump. Did you put in new bushings,and gears, did they have the right amount of back lash between the gears. How much clearance between the gears and the bottom plate.
 


Hi Bruce,


As much oil as the A pump "Flow's", 2 minute's seem's along time to fill up the Valve chamber...I remember cranking the motor over with the hand crank to set the valve's.


Had plenty of oil filling the first "Dam".. This was in a few second's. I can imagine with the engine running !. I was thinking how high is the hole in the front going to the timing gear area ?. If it was too low, I could see most of the oil running out the front



I remember somebody back on the old Fordbarn made a plastic Valve cover to watch the oil flow. He said he was surprised how much oil was coming out at the oil outlet.


Greg out West


 
George,

Also the clearance between the gear and the SIDE of the housing.

Bruce, if the bushings were real bad, the gears will wear the housing on the drive
side.

Dudley
 
Bruce,
The following is a bit long but I want you to have the full picture so you can judge if you have a problem with your pump.
When I start up a freshly re-built engine I usually get oil flow at the lower end of the return pipe within 10-15 seconds of starting the engine. I always verify flow by having the lower bolt loose on the oil return pipe and a small screwdriver holding a gap between the return pipe and the gasket. I also install a pressure gauge in the side of the engine at the oil pump plug to monitor the system pressure both cold and warm. My engine stand holds the engine at the correct tilt (back lower than the front) and I do pour 2 quarts of oil down the distributor hole just prior to start-up. (Usually within 15 minutes of start-up so I do not think a lot of oil has passed through the center or rear bearings that would drain the reservoirs.) With the recent addition of oil through the distributor hole the center and back reservoirs are full of oil, the front reservoir most likely has little to none. At start-up, the pump fills the front chamber and then contributes more to the middle and then rear causing the flow within 10-15 seconds. Two minutes sounds a bit suspicious unless the front of the engine was abnormally low at start up. (Parked on a slope?) Two minutes probably did not do any damage at all to the bearings. I use Rich’s inserts all the time and they are pretty durable.

The following is a quote from Rich’s start up instructions: “Check oil flow immediately after starting engine. If gauge is not used loosen lower oil pipe bolt. Oil should start to spurt out in first minute and half of running. If no oil in two minutes turn engine off. Determine why no oil flow and repair as necessary.”

If you suspect that the pump is not producing adequate flow, I agree with a previous posters suggestion you remove the valve chamber cover and verify the flow from the outlet located in the front reservoir. Replace the pump if it is suspect. There is a chance the oil passage between the pump and the front chamber is restricted from rebuilding debris or hardened sludge. This passage is difficult to clean but it is possible to work a wire into it to clear it. The combination of restriction in the passage and an underperforming pump could give you reduced flow. After you ensure you have adequate oil flow, if you are really concerned about possible bearing damage, run the engine for a couple hundred miles, drain the oil and have it analyzed. I doubt you will find anything from the test.
Did you take the engine as a short-block from Rich? If so, you would have installed the pump and set the pan….so his warranty wouldn’t probably apply if your oil pump was/is bad. If you installed the pan on a short block, removing it to replace a pump is not going to void your warranty.
Good luck with your project.
Dave in MN
 
George Miller said:
You did not say if you are running pressure to the mains and rods. That would make a difference. You say you rebuilt the pump. Did you put in new bushings,and gears, did they have the right amount of back lash between the gears. How much clearance between the gears and the bottom plate.
Click to expand...

Hi George,
A touring engine from Rich (Antique Engine Rebuilding) will not have pressure to the mains and rods. I just spoke to Rich an hour ago when placing an order and he again confirmed he is not doing pressurized engines. I have asked him a couple times over the last three years about performance engines with pressurized bearing feed and his comments were pretty consistant to the following: "I want to market to the 90% of the Model A owners that want a basic engine. I want to leave the exotic stuff to the other guys."
Good point though...if it were pressurized, it may take longer to fill the chambers and have oil in the return pipe.
Good day!
Dave in MN
 
The height of the dam at the front of the engine (where oil spills into the cam gear area) is variable. It looks like part of the original casting that might have been chipped away by Ford to get the proper height. Several years ago I measured this height on 8 or 9 blocks. I will try to find my records on what I found.
 
Thanks to all who responded...lots of great insights.

I am indeed going to replace the pump (and I'll be inspecting all that I can for obstructions, etc.). Is there a perferred pump brand or vendor? I always use Melling pumps on flatehead V-8's; I'm just not sure what I'll get if I order from one of the larger vendors.
 
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