Durant Motors Internet Forum

Our Purpose

  Preserve the automobiles manufactured by the Durant Motor Company, provide enjoyment for each member with meets, tours & technical assistance.


This forum is provided by the Durant Motors Automobile Club located at durantmotors.org

How to Add Pictures             Rocky

General Discussion Forum
Start a New Topic 
Author
Comment
A-22 Oil Pump

For years people in the know complemented me on the great oil pressure on my 22. I assumed it was due to the very low mileage and every thing was tight. I was blissful in my ignorance!!

I removed the oil pump and ran some parts cleaner through it to remove the 80 year of dead oil. When I put it back on the oil pressure was low just like most A-22 owners complained.

I have read the tech article that deals with this issue which states the low presser is due to excessive clearance between the shaft and the housing. It suggests that a bushing inserted between the shaft and bushing will eliminate the problem.

2 questions:
Has anyone attempted this alteration? If so, what were the results?

Can somone recommend a machinist to do the work? My guy is in his 80's and slowed way, way down. He has had a Marvel heat box to re-bush for 7 months now. Work is progressing on it but I don't want to wait for ever to get get my Durant running properly.

Any help or commenents will be appreciated.

Thanks

Lew

Where Are You From? Westminster, MD

Do You own a car built by Durant? Yep, 1922 A-22

Re: A-22 Oil Pump

LEW'
Isn't the A 22 engine a low pressure system. I believe the early gauges were max 5 lb and the later ones 10 lb. How much pressure are you looking for?
We have yet to get our motor running, so don't know how much it will show.
Gord

Where Are You From? Guelph, Ontario, Canada

Do You own a car built by Durant? 1932 Frontenac

Re: A-22 Oil Pump

Lew,
In addition to a worn pump housing/bore it is also important to obtain minimum clearance on the side/cheek plates or gear side clearance and also a minimum tooth to housing clearance...Looking at a worn A-22 oil pump that I have It looks like the housing bore is 7/16" (.4375) and the pump shaft is about(.435) I would think that you could stop by an Auto-Machine shop and ask if they could install a 7/16" bronz valve guide bushing then they can ream to fit your shaft with an undersize reamer if necessary...If not than it's off to a machine shop...Larrys Durant Parts on our Links page has NOS oil pump gears listed.

I have an interesting oil pump on my A-22, someone before me had made a hi-output pump by fabricating an approx. 1/8" extention plate to the end of the pump housing and installing 1/2" wide gears in place of the standard 3/8" gears...I still need 20/50W oil for any kind of pressure when hot and idling.

Where Are You From? Leavenworth, WA/ Yuma, AZ

Do You own a car built by Durant? '23 A-22 Touring / '29 Model 40 Coupe / '25 Flint H-40

Re: A-22 Oil Pump

Bill thanks for the valve guide idea sounds like a good idea so long as there is sufficient metal left after the cut to fit it.
thanks
Lew

Where Are You From? Westminster, Md

Do You own a car built by Durant? Yep 1922 A-22 Touring

Re: A-22 Oil Pump

Lew
Does your car have the early oval oil pump or the later round pump also do you have the early 10lb oil guage or the later 5lb oil guage?
Lastly what did you consider "good oil pressure".
It is my understanding that with a low pressure oil system you want oil flow not pressure ie if it reads high pressure shut motor off because you have a blockage somewhere.
any comments greatly appreciated as I am getting ready to start my car for the first time
Note when I spin the oil pump with a low speed electric drill I get about 2 lbs?

Where Are You From? Guelph, Ontario

Do You own a car built by Durant? 1922 Durant A-22 touring

Re: A-22 Oil Pump

Hi Will my car usually showed 2#at idle and pegged the 10# gauge at speed. this has been the norm for it since new...and i drive it a good deal so i doubt it had a blockage in it.

now it i am lucky if it has 1 # at idle and maybe 4 at speed. Once warmed up it might show 1# at idle or maybe none. At speed it now shows only about 3.... not good

Where Are You From? Westminster, Md

Do You own a car built by Durant? Yep 1922 A-22 Touring

Re: A-22 Oil Pump

Lewis:
The challange now is to determine which is at fault: the gauge, oil pump and feed lines, or excessive bearing clearances.
To start with, I would temporarily tee-in a known low pressure working gauge at the engine to verify oil pressure and dash gauge oil pressure. If that checks out ok, check to see that the over-pressure relief valve and spring are in working order. Next, check that oil pressure feed lines are tight, check oil sump screen is not blocked with debris, dismantle and inspect the pump for wear. The issues in general with oil pumps are, as everyone else has said, is excessive shaft-to-housing clearance, gear thickness-to-housing clearance, gear diameter-to-housing clearance. The remaining issue could then be excessive bearing oil clearances.

Where Are You From? Hyattsville, Md

Do You own a car built by Durant? Yes

Re: A-22 Oil Pump

Steve very good advice, however finding a "known good 10lb guage" may be a little harder. If you were to hook up a reg 50lb guage the needle would hardly move on a known good motor. When I got my car a previous owner had installed a 50lb guage and I had to locate a 5lb guage. As I mentioned earlier I spun the oil pump with a lowspeed drill and woul get about 2 - 3 lbs on different guages, it will be interesting to find out what it reads when I get it running.

Where Are You From? Guelph, Ontario

Do You own a car built by Durant? 1922 Durant A-22 touring

Re: A-22 Oil Pump

Or.. stick a hand held fuel pump gauge on the oil pump These gauges are normally in the correct range

Where Are You From? Westminster, Md

Do You own a car built by Durant? Yep 1922 A-22 Touring

Re: A-22 Oil Pump

Our A-22 engines have what the Operators manual calls a double oiling system known as force-feed and constant lever splash...I see no oil flow chart but looking at an extra engine I have it appears that oil is pumped through a 5/16" distributing tube having 4 approx. 1/8" nozzles directed at troughs located for the rods to dip for their lubercation, this same 5/16" tube also connects below each of the three cambearings which have gallies that connect to the cambearings as well as over to the three main bearings...I see no relief valve in the system...It appears to me that the oil pump requirement would be to supply enough flow for the nozzles and with enough residual back pressure to force lubercation to the cam and main bearings...So I thinking that it is not so important how much oil pressure that you have but that you do have oil pressure of some kind...They were recomending to use a lighter oil in winter and a mid to heavy oil during the summer...Lew, have you tryed using a heavier oil or a multi- viscosity oil like a 20-50w? I do know that with the oil pump being located higher than the oil leavel in the sump, that if the pump shaft/bore gets loose from wear that the pump won't prime, in my case I had an extra housing with a good bore which corrected my problem.

Where Are You From? Leavenworth, WA/ Yuma, AZ

Do You own a car built by Durant? '23 A-22 Touring / '29 Model 40 Coupe / '25 Flint H-40

Re: A-22 Oil Pump

Bill, thanks for taking the time to look up the Durant oiling system. One piece of important information is that it had great, for a splasher, oil pressure for the 90+ years it has been in the family. The motor was pulled down and cleaned in 1956 after which the oil pressure was still fine. We have always used 30W ND in it with no problems. The problem developed only when I pulled and cleaned the oil pump for a non-related reason. So I am assuming I washed out a "Gunk Seal" you know, the kind of seal which is created by years of sludge and gunk accumulation. Thus my assumption that the car has, what seems to be a normal for them, problem: excessive shaft clearance. Of course, it could be something else, such as bad gears or a poor gasket. I am going to contact Larry to see if he still has any oil pump gears.

Also, putting thicker oil in a splasher does not resolve the issue in the same way it would in a pressurized system. In a pressure system the thicker oil will fill a bit of the extra, wear induced clearance in the rods, cam bearings and mains. This will increase the oil pressure but will not fix the excessive clearance. However, in a, splasher with proper clearances, which mine does have, the last thing you want is thicker, slow moving oil. The bearings need the correct amount of oil flowing in and out to stay cool and lubricated. The effect of the thick oil would be to increase the pressure while in the tubes and thereby reduce the flow through the tube... however, the gage would show the increased pressure. The bearings being of correct size would be starved for oil for 2 reasons: The oil would be to thick to get into the bearings through the scuppers and clearance and the decreased flow rate would not provide sufficient quantities of oil. Like you said, pressure is not the issue, it is flow.

Flow is a result media viscosity through an orifice at a given pressure. Increasing the viscosity will slow the flow and increase the residual pressure. Decreasing the orifice diamater will increase the residual pressure (resistance) while decreasing the flow. Increasing the pressure with the same viscosity liquid, will increase the flow. Gosh, I had to dig that out of the old gray matter form engineering school.

I just thought I would pass on this information in case someone reads this and thinks thicker oil is answer and tries it.

Keep the ideas coming and I’ll work through them all.

Exchange of information makes all our hobby lives better,

LEW

Where Are You From? Westminster, MD

Re: A-22 Oil Pump

Lew,

That is the beauty of a 20w50 oil...When the oil is cold it is a lightweight and when the oil is hot it is a heavyweight, the best of two worlds...One other thing, If you have the earlier type oval oil pump as Will has mentioned in an earlier post than the oil pump gear drive slot is square, If you have the later circular pump than the gear will have a slot for a pin drive...The later version is the one that Larry has listed... Bill

Where Are You From? Leavenworth, WA/ Yuma, AZ

Do You own a car built by Durant? '23 A-22 Touring / '29 Model 40 Coupe / '25 Flint H-40

 

The Durant Motors Automobile Club