Jump to content

Low oil pressure after ten minutes of running engine, 1929 135


wayne kinne
 Share

Recommended Posts

After running our 1929 for ten or twenty minutes the oil pressure drops to very near zero. The engine seems to run great and I do not want to tear it apart if there is an easier way. My first question is how much pressure is typical for a 135 after it is warmed up? It starts out around 60 psi but rapidly drops once it is warmed up, it barely registers on an 0 - 80 psi gauge. My thought is to add an external electric oil pump, any thoughts from those who know more than me ( probably everyone here )? I do not know how long this has been an issue, or if it even is. We purchased the car one year ago and drove it several times before noticing the low oil pressure. I asked the guy we purchased it from if he ever had low oil pressure issues and he said he never paid attention to the gauge, he is a good friend and I know he would not lie to me. But he never put many miles on it so it is possible it has been this way for a long time, or it could be a new issue. Any ideas, suggestions, or recommendations? Thanks in advance.

Link to comment
Share on other sites

I can, I was hoping to find a 60 psi max gauge thinking it might be more accurate and the lower end, I have not been able to find one.

Interesting, I just found a 0 to 15 psi oil pressure gauge made for a 1928-1931 Model A. So what would be the expected oil pressure on a 1929 Franklin?

Edited by wayne kinne (see edit history)
Link to comment
Share on other sites

A few questions,...

What viscosity motor oil are you using ?

 

What gauge are you seeing 60 psi on , the one in the dash board, or your 80psi gauge ? 

 

It's likely there is a problem with the gauges reading at low pressure. 

 

Is there an oil filter attached to the engine? If so, it may not have enough restriction to keep enough pressure in the system.

 

The oil filter system is a "by-pass" type, not a full flow like modern cars use. It only gets some of the oil from the pump. If the original pot metal oil filter connection block has been changed to the later elbow fittings it may be the wrong one. The elbow feeding the filter should have a small hole down inside it to help maintain pressure in the system. That elbow is the same as the one to the fuel pump and the vacuum wiper line at the intake manifold. All three elbows look the same but they have different inside diameters. It's not uncommon on restored cars that those elbows end up in the wrong place. If an elbow with a bigger inside diameter is used on the filter inlet it can cause low oil pressure once the oil warms up. 

 

Franklins have very large surface bearings, so they don't need high oil pressure. So what some might think is low pressure in a warm engine, is normal in a Franklin. Should be about 20 psi when hot and an engine speed of 30 mph, with 30W oil.  5-10 psi at hot idle is ok.

 

The 135 has a constant pressure oil pump.  The 130, and before the 135 Franklin engines used a pulsed oil pump system and even though it is not constant pressure system like your 135, they still work fine.   

 

Paul

Edited by PFitz (see edit history)
Link to comment
Share on other sites

2 hours ago, RichardD said:

Realize the post is pre-'31 but on my '31, does this look ok?
Line between cylinders goes to mech. gage. Valve oiler shutoff.
I have never been concerned with it reading low.

 

fRANKLIN OIL PIPING.jpg

Can't tell what the inlet elbow is from that angle, especially and certainly would not be able to see if it has the .060 restriction hole down inside the elbow. Have you ever measured the oil pressure,... cold, hot? 

 

In the 700 section of the 31 owner's manual, it says how to measure and what PSI to expect. The Series 135 manual does not. It only says to disconnect the oil line to the oil filter and if oil flows in "impulses" it is OK. Only problem with that is, that is for the 130 pump which is a "pulse" type pump. The 135 is not a pulse type but a constant pressure type oil pump.  Opps for Franklin proofreaders.

 

Paul

Link to comment
Share on other sites

Ran for about 20 minutes in garage( have hose under door) and oil pressure showed around 26psi reved up and around 20 psi at idle. 
At least it is not low; I rebuilt engine but never removed rods nor oil relief valve; but did plasticgage clearance.
Side note for those that run engine(s) in garage: hose in photo makes me happier. It is from a wet vacuum system that is a perfect fit for the exh. pipe.1140377751_Franklinexhaustdoor.jpg.62522317532d131b86f22717f9212586.jpg

Edited by RichardD (see edit history)
  • Like 1
Link to comment
Share on other sites

The 135 engine is a Pulse pump engine.  Full pressure systems originated with the Series 14. 

An oil pressure reading on a 135 pump can mean very different things based on where the reading is taken. 

The factory did not fit a pressure gauge to the 1929 cars. 

 

  • Like 2
Link to comment
Share on other sites

23 hours ago, PFitz said:

Can't tell what the inlet elbow is from that angle, especially and certainly would not be able to see if it has the .060 restriction hole down inside the elbow. Have you ever measured the oil pressure,... cold, hot? 

 

In the 700 section of the 31 owner's manual, it says how to measure and what PSI to expect. The Series 135 manual does not. It only says to disconnect the oil line to the oil filter and if oil flows in "impulses" it is OK. Only problem with that is, that is for the 130 pump which is a "pulse" type pump. The 135 is not a pulse type but a constant pressure type oil pump.  Opps for Franklin proofreaders.

 

Paul

Paul, Ive owned several 1929s  and none of them were pressurized lubrication. Was the one you worked on a "Special" ? Ive been told that a 1930 pump can be installed in a 1929 engine, but I don't have any first hand knowledge on the subject. 

Link to comment
Share on other sites

20 minutes ago, mikewest said:

Paul, Ive owned several 1929s  and none of them were pressurized lubrication. Was the one you worked on a "Special" ? Ive been told that a 1930 pump can be installed in a 1929 engine, but I don't have any first hand knowledge on the subject. 

Might have been., Mike. I was told the car was owned by a Franklin mechanic for many years - Bill Gewand's 135 Victoria. I seem to remember getting a steady reading at the oil filter line, and not the high-low readings of the earlier engine pulsed pump external oil lines.  

 

Paul

Link to comment
Share on other sites

Wayne, post a photo of the passenger side of your engine so we can see the set-up   What is the engine #?

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...