Oil pressure

[Gadgetman]

Evening all

had a good weekend pretty much finishing off my 1600 engine re-build and finding annoying little nuances that I now need to undo ( I bought a dynamator but it’s shorter than the dynamo  that was fitted to this engine by 1/2”, the one in my car is the same as the dynamator so i now need to swap around brackets and spacers!)

 

anyway to the point:

After filling up with oil I’ve spun up the oil pump with a drill and adapter to prime the oil system.

I had an oil pressure gauge fitted and it was showing 100psi!! 

I removed the pressure relief valve, checked it over and found nothing wrong ( it’s a new spring and plunger). To see if it was sticking / stuck I put the old one back in and it was the same. So as to make sure I didn’t have a blocked oil return from the pressure relief valve I reassembled it without the valve and spring. As I expected I got no oil pressure. 

Anyone any ideas? I’m going to try another oil pressure gauge but I don’t think it’s that.

Do the pressure relief valves need setting up ( washers between the valve body and block) to adjust the relief valve spring tension?? 

[Anglefire]

Mine is 100psi on startup. Hasn't blown up yet.

[Colin Lindsay]

Mine too. Goes right off the scale on startup then as the oil thins it drops back to normal.

[Herald948]

Quick thoughts:

I agree with others that your oil pressure likely is just fine!

On the dynamator, can I assume that your original dynamo (generator) would've been a C40L and that the new dynamator more nearly resembles the shorter C40 dynamo?

Edited October 20, 2019 by Herald948
clarification

[Gadgetman]

15 minutes ago, Herald948 said:

Quick thoughts:

I agree with others that your oil pressure likely is just fine!

On the dynamator, can I assume that your original dynamo (generator) would've been a C40L and that the new dynamator more nearly resembles the shorter C40 dynamo?

Yup one engine has a C40 and the other has a C40L!  Sods law my spacer that’s been plated is for the C40L and the Dynamator is a C40

[Pete Lewis]

let us know how you get on with the dynamator  some here have been  expensive  and troublesome 

Pete

[Gadgetman]

1 hour ago, Pete Lewis said:

let us know how you get on with the dynamator  some here have been  expensive  and troublesome 

Pete

Will do Pete. 

What’s the difference in a C40 & C40L apart from the length??

[daverclasper]

I think it produces 3 more amps.

Dave

[Herald948]

On 20/10/2019 at 15:09, Gadgetman said:

Yup one engine has a C40 and the other has a C40L!  Sods law my spacer that’s been plated is for the C40L and the Dynamator is a C40

Murphy's Law and all that.... (Were Murphy and Sod related?)

[Paul H]

5 hours ago, Herald948 said:

Murphy's Law and all that.... (Were Murphy and Sod related?)

I have a new C40L Dynamator still in the box if you are interested ? 

Paul 

[SpitFire6]

 

 

 

 

On 20/10/2019 at 17:58, Gadgetman said:

SNIP.

anyway to the point:

After filling up with oil I’ve spun up the oil pump with a drill and adapter to prime the oil system.

I had an oil pressure gauge fitted and it was showing 100psi!! 

Snip.

Hi,

 I have never tried this myself.

Did you use a large mains-powered drill?
How did the drill feel when your gauge was reading 100 PSI? I always thought you would need an arm like Popeye. 

Interested in what oil pressure you get with a hot running engine.

Shortening the spring will reduce the pressure. Adding washers between spring & head will increase the pressure.

Surprised a "waxstat" for th valve has not been invented.

Cheers,

Iain.

PS. Need not mention the O word once.

[Gadgetman]

Used a De-Walt 18v cordless drill but

it killed the battery after 2 minutes!

i had to keep a lot of down pressure on the drill to keep it engaged in the oil pump!

i’ll warm the sump I with a 2KW fan heater to get the oil up to temp and see what the pressure  does.

id look at putting an extra copper washer under the valve body if I needed to drop the pressure, but going by what everybody is saying I’m probably ok  as is .k

I’m now looking at pressurising the water system before I fit the engine to check the core plugs for leaks. Probably going to turn up aluminium blanks for the water hoses and then tap one to take a screw in schraher tyre valve.  Then pump air in up to 7 psi and leak check with soapy water....

[Nigel Clark]

Which way did you spin the oil pump? It needs to be anti-clockwise.

When I built a 6 cylinder Triumph engine recently, it needed less than 10 seconds spinning the oil pump anti-clockwise with a drilll  at low speed to get pressure.

Nigel

[thescrapman]

Fully charged 18v Makita in reverse and it slows almost to a stop as the pressure suddenly builds up.

I use a salvaged PI dissy drive shaft as it is obviously designed to engage on the oil pump

[Pete Lewis]

I can visualise the engine build at triumph with loads of guys with drills to prime the engines on their test beds on production

I dont think that was part of the production process,  bear in mind most were probably run on gas and it was common practice to run engines back to back ,, one drove the other , some never ran on their own power  let alone prime the oil  chest

They  probably all had start up knock  but know one noticed with all the noise, remember they have only lasted 50 years even with a few rebuilds 

Its a must have thats desireable to some,   but in the end pretty unnecessary

Pete

 

[Gadgetman]

Trouble is Pete its multiple OCD (Obsessive Compression Desire 🤣) it comes from working on aircraft for years and wanting to make everything as perfect as possible. 

[thescrapman]

Pete, I have been doing it because my TR6 oil pump will not self prime after a filter change.No idea why, but the engine coming out to investigate is much closer after my attempts due to the damage I have done prior to realising there is a problem.

once the pressure comes up for the first time never a problem until the next oil change.

As for rebuilt engines, I am with Mr Gadgetman, I would do it just to make sure the pump works.

[JohnD]

Unless you are an F1 trained technician, used to four wheel tyre changes in less than two seconds, with at least one assistant, there is plenty of time while you reassemble the dizzie and fit it, for all that oil to fall back into the sump.    I prefer to turn the whole engine over on the starter, no plugs in so minimal stress, whip the plugs back on and go for a start.

It helps if you use a running modern with jump leads connected, so plenty of juice for the whole procedure.

John

[Pete Lewis]

john   thats a yes from me    ha !

[daverclasper]

Yes. I do that. It doesn't take that long for the oil light to go out and battery seems to take it easily (just for a filter change).

Dave

Edited October 25, 2019 by daverclasper

[johny]

9 hours ago, thescrapman said:

Pete, I have been doing it because my TR6 oil pump will not self prime after a filter change.No idea why, but the engine coming out to investigate is much closer after my attempts due to the damage I have done prior to realising there is a problem.

once the pressure comes up for the first time never a problem until the next oil change.

As for rebuilt engines, I am with Mr Gadgetman, I would do it just to make sure the pump works.

You mean you put in a new filter and oil then start the engine and no pressure shows? It does take a few nerve racking seconds to fill the filter and system but can't think of any explanation why the pump would prime by hand and not on starter....

[thescrapman]

On 25/10/2019 at 12:37, JohnD said:

Unless you are an F1 trained technician, used to four wheel tyre changes in less than two seconds, with at least one assistant, there is plenty of time while you reassemble the dizzie and fit it, for all that oil to fall back into the sump.    I prefer to turn the whole engine over on the starter, no plugs in so minimal stress, whip the plugs back on and go for a start.

It helps if you use a running modern with jump leads connected, so plenty of juice for the whole procedure.

John

Tried that John, flattened 3 fully charged batteries and had it jumped off a running car, plugs out, still would not pressurise.

oil pumped back in the pressure switch hole, fully brimmed new filter. Everything I could think of.

couple of minutes wit the drill sorts it.

there is definitely something wrong with the pump, just need to get the engine out to see what.

[thescrapman]

19 hours ago, johny said:

You mean you put in a new filter and oil then start the engine and no pressure shows? It does take a few nerve racking seconds to fill the filter and system but can't think of any explanation why the pump would prime by hand and not on starter....

Few nerve wrecking seconds, more like 2 minutes and I bottled out. That is why the ends now rattle and theoils pressure dips alarmingly when hot.

[Pete Lewis]

i would agree on drill or on starter is same , is the pressure relief valve stuck open ??  so youre just pumping back tot the sump ??

pete

[JohnD]

If this after a full rebuild, gave you checked BBB the bell housing?   Leave out the plug from the back of the main gallery, and the housing will be full of oil.

No need to ask me how I know.

John