Low oil pressure 13/60

[Antonnick]

It can be big mistake to fit instruments - then you can see all sorts of things in an old car that maybe are not right. which you did not know about before. 🙁

I have fitted an oil pressure gauge to my 13/60 which shows about 55 PSI when cold but which when warmed up shows only an alarming 20 to 25 PSI at 80km/hr and at idle less than 10 PSI. I have had the car for about a year. From the previous engl. MOTs Mileage it has done only 400 miles in 12 years. The oil and filter I changed as soon as I got it.

I have to say that it starts without any problem and does not make any strange noises. Neither is the performance lacking in any way. However I do fear the worst. The oil does need topping up after about 200km but not very much, say 50 mL. It may be dripping more than burning it!

The first thing I intend to do now is to remove the oil filter and cut it open to see if it is clogged. Although it has only done 1500km, there is a possibility to my mind that the previous infrequent usage has left sludge throughout the engine. The other thing I intend to do is to remove the sump and see if it too is clogged with sludge - at the same time I can check the the oil pump and maybe, if it has one, the gauze filter.

Would the above be a logical first step before condeming the motor to a rebuild? For what it is worth the original mileage read 14000 but whether this is 114000 or 214000 is any body's guess.

[nang]

While you have the sump off, it may be a good idea to drop a big end cap off and have a look at the shells. if they look like copper (as mine did) time to measure the crankshaft for wear.

Sorry if you didn't want to know this. 

Tony.

[Clive]

Not a bad idea to drop the sump, most I have looked at had a thick layer of sludge, which is never good.

And as Tony says, a new set of big end bearings may well improve things a lot, pretty easy to do once you are under there. In fact you can change the main bearings too if you are careful. A re-bearing will give many years of service.

Also worth checking the oil pressure relief valve is seating correctly, if that is jammed open a little it won't help, and lack of use could cause that to happen.

Lastly, are you using the correct grade of oil? 20-50?

[Antonnick]

Thankyou for the tips Tony and Clive. Yes I am using 20/50 oil.

I will study the workshop maual and put my dirty dungarees on next week and have a look.

 

[Nick Jones]

Is the gauge a reputable make?  Mechanical type or electrical?  Might not be giving a true reading?

Well worn Triumph engines very often knock a bit on first start of the day - does yours?

Assuming your gauge is giving a true reading, with near 10 psi hot idle (not too bad for a well used engine) but only 20 - 25 psi at 2000 rpm +, I reckon you might need to renew the relief valve spring.

Never a bad idea to drop the sump and clean it out.  My tip on that would be to get the car warm and then leave the oil draining over night before starting the job.  And a good, oil-proof hat.  Used 20/50 is lousy hair conditioner.

Also, the centre and rear main bearings are reasonably easy to change with the engine in the car, but the front one means disturbing the bridge plate  and it's gasket with the front plate - very hard to seal effectively afterwards.  Therefore, unless the other two bearings are really worn I tend to leave the front one alone as it is the least loaded and usually the least worn.

Change the thrust washers on the rear main at the same time.

Nick

[Guppy916]

As Nick said check the mains, and while the relief valve is out stick a 14mm twist drill in the hole and give it a few twists by hand to clean the valve seat,

mine is 14mm on a 2.5 yours might be different

[Antonnick]

More good advice - many thanks. To answer the questions.

Mechanical gauge is new from Rimmers but has the braided 1,2m piping from mini Spares.

No, the engine does not knock on first start up. A  intermittant rattling sound does come from the direction of the Bonnet but I feel it is a loose fixing somewhere, not directly to do with the engine itself.

 Actually I did hope for such ideas from the forum and I am very pleased to read the tips which give me something to work on - I have made a list of items to be ordered from Rimmers  incl sump gasket, filters and now the spring but the bearings and thrust washers are available it seems in oversizes. I suppose I need to do some measurements after removing the old ones before diciding which to order. I will check the manual unless there is a good tip.........hint, hint 😆

[nang]

You really need to measure the crankshaft for ovality and check it for score marks on it. Just have a good look at the bearing shells first though. 

If there is much sludge in the sump it may be time for an engine flush.

Tony.

[nang]

Just found out how to make the print bigger 😆

Tony.

[glang]

Quoted from Antonnick-

It can be big mistake to fit instruments - then you can see all sorts of things in an old car that maybe are not right. which you did not know about before. 🙁

I have fitted an oil pressure gauge to my 13/60 which shows about 55 PSI when cold but which when warmed up shows only an alarming 20 to 25 PSI at 80km/hr and at idle less than 10 PSI. I have had the car for about a year. From the previous engl. MOTs Mileage it has done only 400 miles in 12 years. The oil and filter I changed as soon as I got it.

I have to say that it starts without any problem and does not make any strange noises. Neither is the performance lacking in any way. However I do fear the worst. The oil does need topping up after about 200km but not very much, say 50 mL. It may be dripping more than burning it!

The first thing I intend to do now is to remove the oil filter and cut it open to see if it is clogged. Although it has only done 1500km, there is a possibility to my mind that the previous infrequent usage has left sludge throughout the engine. The other thing I intend to do is to remove the sump and see if it too is clogged with sludge - at the same time I can check the the oil pump and maybe, if it has one, the gauze filter.

Would the above be a logical first step before condeming the motor to a rebuild? For what it is worth the original mileage read 14000 but whether this is 114000 or 214000 is any body's guess.

You can get an idea of the wear on the thrust bearings and maybe the entire engine by moving the front pulley in and out by hand or possibly with a lever. There should be just detectable play not a loud clonk which if present indicates youll need new thrusts (but unfortunately not which size) and also that the engine has done more than 14000 miles

Also dont forget that, if necessary, you can avoid replacing the oil pump if its ok except for axial play (often the case) as its possible to remove metal from the body to bring it with tolerance

[RobPearce]

The easiest way to figure out what size bearings you need is to look at the ones you take out to see what size they are. If the current bearings are in "OK" to "a bit worn" state (perhaps a hint of copper showing but no scoring or squishing) then fitting a new set of the same size will help. Anything worse than that, and certainly anything hinting at a different oversize, will require the crank to be reground.

Thrust washers are a bit harder. My usual method, there, is to buy a set of each available size and fit the pair that gives the right end-float. If that's a single size pair, the unused ones go back for a refund (I buy them at TRGB because they're local). If I had to mix-and-match, I just keep the others as spares.

[daver clasper]

Hi. As far as I am aware oil pressure in the bearings, is not connected to an engine burning oil in the cylinders.

Dave

[Matt306]

MY 13/60 was suffering the same problem. I dropped the sump, the crank was grooved and could have done with a regrind, but whacked new bearings in and the pressure is still good. I did the C2C in it a few months back too..

I do accept the bearings will wear sooner with the crank not being ground.

[glang]

I do think burning oil is usually a good indicator of general engine condition which would fit with a diagnosis of worn bearings.....

[Bitumen Boy]

Hi Antonia,

Plenty of good advice here as usual, but from my own experience I would advise against dismantling your engine just yet. I've had my 1200 for a good many years now and one of the first things I did was to fit an oil pressure gauge. Always had good oil pressure until one day a couple of years ago, when I did a routine oil and filter change. Cold oil pressure was normal, but once hot it was down to the sort of level you're seeing. I figured it had to be either the oil or the filter as it happened immediately after the change. Another lot of fresh oil made no difference, but replacing the filter returned the oil pressure to normal levels.

 

The first filter that caused the problems was an aftermarket jobbie, box was branded "classic gold" though the filter itself may have been unmarked - I forget now. The replacement filter that solved the problem was NOS picked up at a show somewhere - enough said. I've since gone down the Mann filter route, but if that's not an option I'd suggest you look out for a NOS filter and try fitting that, it might not be anything more serious. Touch wood, my engine seems to have suffered no damage but time will tell!

[RobPearce]

Dan makes a good point. You said you were using 20/50 oil but not what brand. I have found that most available 20/50 gives very poor oil pressure within a couple of hundred miles of use. Get some Millers, Penrite or similar high quality stuff to go with the Mann filter.

[Antonnick]

I have not been able to start on doing anything yet, nor have I ordered any bits - hopefully later today.

But Mann filter it is then. The 20/50 oil I put in originally may well have been a cheaper sort . I do not really remember but I have Liquid Moly now for the upcoming change. It is most unlikely I will find a NOS (new old stock???) here.

Based on everyone's advice ( vielen vielen Dank!) here is the plan.

Drain oil out, remove filter.

Remove sump and clean it. Remove oil pump just to check and clean it. Remove and clean oil pressure releif valve and use new spring.

New Mann filter and my LM oil.

Make a short test run.

If the low pressure persists, off with the sump and renew the bearings. The oil and filter will only have done about 20 to 30km so can be reused.

I will post some pictures as progress goes along.

Thanks again for all the interest and help

Gruß

Antonia

 

[PeteStupps]

Reading this thread with interest, as I had low oil pressure on my mk3 Spit - as indicated by the idiot light flickering at hot idle. Tried changing pressure-relief spring and oil-light switches but made no difference. 

Took sump off and found main bearings worn through to the copper, so renewed them, the big ends and thrusts. Plus ground the oil pump bottom plate, which was scored. Also cleaned out the sump sludge, and painted the sump pan. Then new oil (cheap) and filter (cheap).

Whole job took me 2.5 days in the garage, spread over two weekends. That includes doing the awkward front main bearing, and heli-coiling the alloy sealing block after I stripped the threads! Highly recommend using a car-creeper and goggles! And a hat.

Unfortunately this weekend I noticed the oil light flickering again at hot idle, so I've still got a problem. (The work was definitely needed though so I'm not feeling too bitter)

The point I'm very interested in is about the quality of oil filter making a difference. Is the oil pressure gauge take-off between pump and filter, or after the filter? If it's after the filter then an overly restrictive filter would be a problem. This is not something I had considered before.

[RobPearce]

Yes, the oil route is:

- up into the pump, at the bottom of the distributor pedestal

- past the pressure relief valve and off to the left, to the filter

- through the filter and into the gallery

- along the gallery to all the bearing feeds, and the pressure switch

[Guppy916]

so is the bottom of the distributor pedestal the place to remove the oil galley plug and fit the oil pressure gauge take off

[Antonnick]

Today I drained the oil and removed the sump which as expected had a nice sludge layer in it. Then I unscrewed the oil filter and cut off the end to inspect the innerds. This too was a bit sludgy but I was expecting to find a thick mess - this was not the case.

Next I unscrewed the oil pressure relief valve but could not remove it because part of the chassis is in the way. 🙁. Only by trying to jack up the engine a bit was there enough free room to get it out. Again it looked a bit sludgy but not that bad.

I then unscrewed the three screws holding the oil pump in place. It came out easily and looks in good condition - will check the tolerances later. Did not find any gauze filter.

I am going to check the big end bearings tomorrow.

The main bearings I am not sure about. How do you get the existing shells out and indeed replace with new when they are buried on the unseen underside of the crankshaft? All this without disturbing or removing the crankshaft. Do you need to rotate the crankshaft also when changing the shells? 🤔

Perhaps it will become obvious once the bolts are removed but at the moment I am a bit confused.

[glang]

With the main bearings once the cap is removed you can gently tap or even push the top half shell round the crankshaft using something soft (plastic) to avoid damaging the surfaces. Remember the shells are not clamped in place but retained by the groove and small lug at one end so that the new ones should if well lubricated slide back round into place.

[Guppy916]

to remove the mains, loosen all the main bearing caps a few turns, then remove one cap both bolts, and jiggle the cap off , then you can push round the top bearing shell to remove it and slide a new one in, you might have to pull down on the crank to ease the shell out,

BUT

before you do this check the crank end float first as new thrust washers may be required

and smear the new shells with oil before you fit them, so get your dirty dungarees back on kiddo 

oh a hat and safety specs are useful when you are down there looking up

[PeteStupps]

Getting the bearing caps off is a bit awkward - unscrew the bolts but don't fully withdraw them. Then use the bolts to wiggle and pull the cap off. 

As above, sliding the old bearings out isn't too difficult. I struggled getting the new ones in, they are a tighter fit and your hands will be all oily! However with patience you can feed them round, rotating the crankshaft a bit while pushing.

Are you doing big-ends as well? Take great care if you rotate the crankshaft with any con rods disconnected: the dangling rod can easily get wedged up against the crankshaft big end journal and dent it slightly. I did this myself on an engine out of the car 😭, and it looks like a previous owner did the same on my Spitfire. 

[nang]

I've only changed the mains on a Rover 2000. Loosened the whole lot first then pushed the shells out with an ice cream stick. Not the easiest of jobs bot it can be done. 😭

Tony