[Rayg]

hi all, have a few problems i cant sort on my 76 Bonny so am looking for some advice, i had the engine stripped and rebuilt using 60thou over pistons, Morgo oil pump,SRM oil pressure release valve as well as all the usual new internals,bearings bushes etc. I also use an internal paper oil filter, and oil pressure guage that comes with the Triples Rule guage set up. Pressure gets no higher than 40psi at top speed and around 25 at idle. After about 100k of riding the pressure drops to 0 at idle and on examination of the oil return has a very weak return flow. I also have a Hyde oil cooler fitted. Cant figure it i thought i had done everything to ensure cool running. Also fitted new Amal carbies as standard, right carby is ok but the left wont flood on tickle and has a very tight air mixture screw, only add on was Viton tipped needles, float levels are 2mm below lip. Any suggestions would be much appreciated.

Ray

 

[GrandPaulZ]

I would suspect the oil pressure relief valve, pressure guage and/or oil pump is malfunctioning.

Remove the new pump, OPR & oil cooler, re-install the old stuff and check it again. If results are the same, try a different guage that has been tested elsewhere.

Too wierd for words...

 

[mark61120]

Oil pressure

Could also be a blockage such as the sludge tube. Whatever it is, DON'T run the engine!!!!
Mark

 

[Mastiff-man]

On a cold start what does it do???



MM

 

[pookybear]

I also use an internal paper oil filter,

Ray

Ray,

That filter is it on the suction side or the scavange side of the
pump?

Pookybear

 

[Rayg]

On a cold start what does it do???



MM

From a cold start it runs straight up to 40psi and will idle at about 20-25 but as the engine gets hotter the pressure drops down to 0-5 At highway speed it will stay around 40, forgot to mention i am using Valvoline 20w-50,

 

[Rayg]

Ray,

That filter is it on the suction side or the scavange side of the
pump?

Pookybear

The oil filter is internal, in place of the standard metal gauze, i have replaced it with a new standard gauze filter with no difference to the low pressure.

 

[Rayg]

Could also be a blockage such as the sludge tube. Whatever it is, DON'T run the engine!!!!
Mark

Hi Mark,
Mate the sludge tube was replaced when rebuilt, or was supposed to be, i was certainly charged for it so can only hope that it was done.

 

[Rayg]

I would suspect the oil pressure relief valve, pressure guage and/or oil pump is malfunctioning.

Remove the new pump, OPR & oil cooler, re-install the old stuff and check it again. If results are the same, try a different guage that has been tested elsewhere.

Too wierd for words...

Hi GrandpaulZ.
Mate i will do as suggested and see what happens, sure hope it is one of those as i would hate to have to split the cases again, many thanks to all for your time and consideration of this issue.
regards Rayg

 

[crazywelder72]

i am curious as to what you find out, as this just happened to me today.

i was out for a ride and when coming to a red light at idle i saw i had zero psi oil pressure. i instantly felt sick to my stomach however i brought up the rps a bit ad i was able to get about 25 psi no problem. i scooted home and at every stop i would keep the rps up just a bit to maintain that 20+ psi.

usually in the past i would have at least 20 psi at idle but i think it was closer to 40 psi at idle and upwards of 60-70 when revved. i have been all over the workshop manual this evening as i am trying to start with the easiest checks first but i haven't done a thing yet. the manual talks about everything from wet sumpping to oil pressure check valves. what do you recommend checking first.

 

[Rayg]

i am curious as to what you find out, as this just happened to me today.

i was out for a ride and when coming to a red light at idle i saw i had zero psi oil pressure. i instantly felt sick to my stomach however i brought up the rps a bit ad i was able to get about 25 psi no problem. i scooted home and at every stop i would keep the rps up just a bit to maintain that 20+ psi.

usually in the past i would have at least 20 psi at idle but i think it was closer to 40 psi at idle and upwards of 60-70 when revved. i have been all over the workshop manual this evening as i am trying to start with the easiest checks first but i haven't done a thing yet. the manual talks about everything from wet sumpping to oil pressure check valves. what do you recommend checking first.

Hi crazywelder,
Mate as luck would have it i have just returned from a test ride, as suggested in this forum i checked the oil pressure release valve first and found that to be the fault, i was very suprised as it was a new one from SRM, there was no trace of dirt of any kind so will have a chat to the guys at SRM and see if i can return it to them for imspection to see if it was just a faulty part. I replaced it with a standard OPRV started up and it went straight up to 75psi, on the road at 100kph it stayed around 70psi and approx 25 at idle, hope this of assistance to you.

Rayg

 

[Rayg]

I would suspect the oil pressure relief valve, pressure guage and/or oil pump is malfunctioning.

Remove the new pump, OPR & oil cooler, re-install the old stuff and check it again. If results are the same, try a different guage that has been tested elsewhere.

Too wierd for words...

Hi GrandPaulZ,
Thanks for the suggestion, I replaced the SRM OPRV with a standard item, problem solved, pressure went straight up to 75psi and 25 at idle, could detect no dirt or grit in the SRM OPRV so will give SRM a call to see if i can return it so they can check it for faults, thanks again for everyones input.

Rayg

 

[crazywelder72]

Rayg,
Thanks for the info... i'll start there. my oprv is the original. who or what is the SRM company that you bought yours from?

i was able to tinker with it a bit today and on a cold start it shot right up to 40 psi (as it should and use to) it took about 10 minutes of running to get warm enough to duplicate the problem again. it dropped to 20 psi at idle and would increase to 40 with as little as a 200 rpm increase.

I didn't see the point of continuing the test and getting it any hotter to just watch the idle oil pressure drop to zero. i guess the next step is to pick up the gaskets i will need for the OPRV so i can reinstall it after inspection (unless anyone has more suggestions)

 

[Rayg]

Rayg,
Thanks for the info... i'll start there. my oprv is the original. who or what is the SRM company that you bought yours from?

i was able to tinker with it a bit today and on a cold start it shot right up to 40 psi (as it should and use to) it took about 10 minutes of running to get warm enough to duplicate the problem again. it dropped to 20 psi at idle and would increase to 40 with as little as a 200 rpm increase.

I didn't see the point of continuing the test and getting it any hotter to just watch the idle oil pressure drop to zero. i guess the next step is to pick up the gaskets i will need for the OPRV so i can reinstall it after inspection (unless anyone has more suggestions)

Crazywelder,
Mate sounds like the problem is with the OPRV same as mine, if you Google SRM engineering and follow their site that will get you what you are after. They are a UK company doing restorations and sell a lot of Brit parts.

Rayg