The Triumph Dolomite Club - Discussion Forum

Hello Dolomite owners, needing some advice regarding the Sprint engine.
I have owned various Triumphs including my TR5 for over 40 years, but they all have had a chassis and pushrods. I recently bought a TR7 with a Sprint engine to have a go hillclimbing and sprinting so I'm on a bit of a learning curve.
My first task was to helicoil nearly all the head tappings and adjust the tappets. It is fitted with a Kent fast road cam and on the rolling road produced 141 BHP which I thought quite respectable and far more than I expected.
On a recent track day, the oil pressure light started flickering under heavy braking and it then wouldn't idle as I nursed it back to the pits. It still turned over on the starter so wasn't seized and all the fluids remained in their proper places which was encouraging.
Fitting an oil pressure gauge was on my 'to do' list but hadn't made it to the top (TR7 does not have one). Back home I fitted a gauge and I was able to get her started and got maximum 20 psi. Not great.
Drained the oil - nothing untoward showing in the oil.
Having discovered the oil pump was on the outside of the block (what!) I ordered a new one to try along with the shorter relief valve spring as suggested by Robsport.
Put some new oil and oil filter in and with the short spring I get 40psi cold - not really enough.
So I tried the long spring. This gave me 70psi but I was immediately aware of a whirring noise in the block in the area of the jackshaft.
I think the engine will have to come out to check the bearings as a minimum but I'm intrigued by the noise from the side of the engine. What is the effect of high oil pressure on the jackshaft?
What should I be looking for as typical issues on the slant four?
Cheers,
Jerry

You need to be careful not to get too much oil pressure as it can cause wear issues on the jackshaft and the thrust plate that holds it in. That shorter spring is the one you should be using normally.
You might want to investigate some sump baffling if you are getting surge problems on cornering, there are some racers on here who can advise about that.
Silly question, are you sure the oil level is correct?

Sent you a PM Jerry...

dursley92 wrote: ↑Sat Jun 04, 2022 1:21 am You need to be careful not to get too much oil pressure as it can cause wear issues on the jackshaft and the thrust plate that holds it in. That shorter spring is the one you should be using normally.
You might want to investigate some sump baffling if you are getting surge problems on cornering, there are some racers on here who can advise about that.
Silly question, are you sure the oil level is correct?

I've only recently fitted sump baffling to mine

Dave

Russ, no such thing as a silly question.
Plenty of oil in the sump, however is it normal on this engine to have the dipstick in a flexible tube that looks like a bit of heater hose? Clearly the wrong length hose would give an incorrect level.
Thanks for the replies and PM.
Jerry

What oil do you use?

Needing to helicoil all the threads in the head does show how and by what person the engine was actually build?

Why wasn't it running anymore? The old school fuelpump safety switch by the oil pressure switch?

Jeroen

JerryTR5 wrote: ↑Sat Jun 04, 2022 10:50 pm Russ, no such thing as a silly question.
Plenty of oil in the sump, however is it normal on this engine to have the dipstick in a flexible tube that looks like a bit of heater hose? Clearly the wrong length hose would give an incorrect level.
Thanks for the replies and PM.
Jerry

The rubber tube was a TR7 thing. Be easy for someone to get that the wrong length. Dolly Srints have a short solid dipstick like this.

Apologies for delay - life gets in the way sometimes.
Anyway, started stripping the engine. Mains & big ends are shot. Jackshaft & water pump gears are damaged.
Just been looking at old threads re EWP and no doubt I will be on the blower to Shaun and back here with more questions.
Thanks for the dipstick photos Russ, something to check.
Jerry

JerryTR5 wrote: ↑Tue Jun 21, 2022 10:39 pm Apologies for delay - life gets in the way sometimes.
Anyway, started stripping the engine. Mains & big ends are shot. Jackshaft & water pump gears are damaged.
Just been looking at old threads re EWP and no doubt I will be on the blower to Shaun and back here with more questions.
Thanks for the dipstick photos Russ, something to check.
Jerry

If you decide to stay with a mechanical set up I can most likely find you a good used water pump shaft and possibly quality bearings depending upon size?