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My tale of woe and possibly intrigue


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Think you are having a bad week ?. Let me tell you how mine is going..

 

Yesterday was the big day. After 6 moths of work the engine was going to be started. It looked great, newly rebuilt, newly painted, 3xDCOE webers, engine bay all refurbed.

 

This picture is from a couple of days ago before I finished the carb installation but it is close to the final configuration:

 

http://i38.photobucket.com/albums/e119/fos...neandWebers.jpg

 

 

We installed the battery, turned the key and it started instantly, faster than I have ever known it to start. It took a few seconds to drop the idle down to 2k rpm where we wanted it to run for about 20 mins to break in the cam and it sounded wonderful. No bad noises from the bottom end, just a bit of clatter from what is probably a poorly adjusted rocker.

 

About 1 minute after starting I decided it would be good to make sure we had oil getting to the new roller rockers. By 1 minute 20 seconds I shut off the engine. The rockers were running on assembly lube and there was no oil getting to the head.

 

We pulled the plug from the oil gallery at the back of the head and cranked the engine. Still no sign of oil.

 

We removed the rocker assembly and checked that the pedastal oil way was clear.

 

We pulled the head thinking that the gasket was installed incorrectly, no problem there.

 

With the head off we verified that the oil gallery in the head is clear. No problem there.

 

Now this block was fitted with the spit cam bearings as part of this project and it has a new cam. In retrospect the spit bearings were an unnecessary step and this problem is somewhat self inflicted.

 

The machinist says that he is pretty sure he checked that the rear cam bearing was installed correctly because he used a flashlight and could see the light at the other end. For reasons that escape me we never verified that fact before we installed the cam

 

I am close to pulling the engine and tranny again but before I do that I wanted to check in here to see if anyone could verify that there is a line of sight between the oil hole in the top of the block and the hole in the cam bearing surface such that with the cam removed you could run a wire though that oil way from the top and see it appear in the cam bearing ?. If that was the case I could at least verify that the cam bearing is the problem.

 

 

Other than a poorly installed cam bearing, is there anything else that that might be causing this that we have not already ruled out or considered

 

Is 1 minute and 20 seconds a TR Register record for the shortest time an engine ran before it had to be stripped down and rebuilt ?

 

Stan

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Think you are having a bad week ?. Let me tell you how mine is going..

 

My TR6 week has been negative but I wouldn't swap it for yours.

So sorry to read this, although you should be proud of your vigilance....

 

Don't know the answer re the cam bearing, and can't find it in the Forum (I dare say you already looked).

 

This is totally off the wall - an external rocker oil feed is generally reckoned a bad thing - but if your internal feed is blocked - could you fit an external feed instead - and could you do this without pulling the engine - I think you could....

 

Just an idea.

 

Ivor

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An external oil feed may not be a bd thing, IF the rockers and shaft are new/nomimal, AND you fit a restrictor to the external feed. Just how small the restrictor should be I cannot say for sure, but less than a millimeter as an orifice may be about right.

John

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- could you fit an external feed instead -

 

Ditto on the "TR week" and now its Friday the 13th!!! :angry:

 

On the subject of the external oil feed, I didn't think this mod directly lubricated the rocker shaft which is what would be needed.......does it?

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My TR6 week has been negative but I wouldn't swap it for yours.

So sorry to read this, although you should be proud of your vigilance....

 

Don't know the answer re the cam bearing, and can't find it in the Forum (I dare say you already looked).

 

This is totally off the wall - an external rocker oil feed is generally reckoned a bad thing - but if your internal feed is blocked - could you fit an external feed instead - and could you do this without pulling the engine - I think you could....

 

Just an idea.

 

Ivor

 

My concern with the external feed is that if the problem was in the rear main or the cam bearing then I have a bigger problem than oil getting to the rockers.

 

I'm actually begining to wonder if I didnt panic too soon. I say this because tonight I started stripping the motor in preparation for pulling the cam out to test that the rear cam bearing is installed correctly (I believe if it is I should be able to poke a wire from the top of the block into the cam bearing orifice).

 

When I removed the timing cover, guess what, no oil here either.

 

So heres the million dollar question.

 

New engine, zero oil in any gallery.

New oil pump

Spin on oil filter was pre-filled with oil

 

Assuming that nothing had been done to build pressure prior to starting and we went from zero to 2krpm without so much as the engine cranking on the starter for more than one rotation, how long would you expect it to take before you see pressure at the gauge and how long after that do we see oil at the head and in the timing cover ?.

 

The reason I am begining to have doubts is that although I did see oil pressure there was a lot going on and I may have seen the oil pressure needle moving past 50lbs at the time when I shut the engine down that last time after about 1 minute 20 secs.

 

As we were testing we did crank the engine on the starter looking for oil in the head etc but we didnt let it crank for more than a few seconds and stopped when we saw no oil.

 

 

This whole thing could have been a simple case of the engine starting without having the benefit of cranking for a while and me panicking !.

 

What do y'all think ?

 

Stan

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Hello Stan,

 

there is obviously something amiss, and I would make up an attachment so as to drive the oil pump with a drill and then follow the oil circuit to pinpoint the blockage. (This may avoid the need for a full strip down?) One thought, could the pressure relief valve be stuck open?

My usual way is to just crank the engine with the plugs out until I see oil pressure build up before starting the engine. You can actually hear the engine quieten down as the pressure builds up, but as you have had some running time at relatively high revs I would go the drill option to minimise the risk of damage.

 

Alec

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Did you prime the oil pump before starting?.I was advised to fit an external oil feed to my rolling rockers and tufrided rockershaft.I must admit when I did this to my then TR6 I used a smaller oil hole in the banjo so it did restrict the flood of oil to the rockers.Hope you find the cure.

Regards Harry TR5 Nutter. :rolleyes:

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Ah Ha!

 

Priming the pump - use vaseline! It dissolves on engine oil far better than grease, and won't leave 'clots' to block up oilways.

BUT, starting a new engine, I would always run it on the starter, with no plugs in or ignition, until oil pressure develops.

 

Then the strain on the main bearings is minimal, and the oil pump has time to 'pump up'

 

John

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My concern with the external feed is that if the problem was in the rear main or the cam bearing then I have a bigger problem than oil getting to the rockers.

 

I'm actually begining to wonder if I didnt panic too soon. I say this because tonight I started stripping the motor in preparation for pulling the cam out to test that the rear cam bearing is installed correctly (I believe if it is I should be able to poke a wire from the top of the block into the cam bearing orifice).

 

When I removed the timing cover, guess what, no oil here either.

 

So heres the million dollar question.

 

New engine, zero oil in any gallery.

New oil pump

Spin on oil filter was pre-filled with oil

 

Assuming that nothing had been done to build pressure prior to starting and we went from zero to 2krpm without so much as the engine cranking on the starter for more than one rotation, how long would you expect it to take before you see pressure at the gauge and how long after that do we see oil at the head and in the timing cover ?.

 

The reason I am begining to have doubts is that although I did see oil pressure there was a lot going on and I may have seen the oil pressure needle moving past 50lbs at the time when I shut the engine down that last time after about 1 minute 20 secs.

 

As we were testing we did crank the engine on the starter looking for oil in the head etc but we didnt let it crank for more than a few seconds and stopped when we saw no oil.

 

 

This whole thing could have been a simple case of the engine starting without having the benefit of cranking for a while and me panicking !.

 

What do y'all think ?

 

Stan

<_< Hello Stan

 

Lets do the right way ?

 

1st of all well done on getting the cam timeing spot on sure sign instant start

You should have used running in oil with a filter with no pressure valve ,primed the engine plugs out.When you have oil pressure start run at 2500 rpm 20 minuets .Change oil and filter and your off.Which cam have you used? this may be important to try and help you out. It is not a disaster yet Stan

 

Regards

Neil

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<_< Hello Stan

 

Lets do the right way ?

 

1st of all well done on getting the cam timeing spot on sure sign instant start

You should have used running in oil with a filter with no pressure valve ,primed the engine plugs out.When you have oil pressure start run at 2500 rpm 20 minuets .Change oil and filter and your off.Which cam have you used? this may be important to try and help you out. It is not a disaster yet Stan

 

Regards

Neil

 

The cam is a new (not reground) Goodparts GP2. It will be coming out shortly for inspection and to probe for the oil path through the rear cam bearing.

 

Stan

Edited by foster461
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I would always run it on the starter, with no plugs in or ignition, until oil pressure develops.

 

That's what I did, having simply filled the spin-on filter 1st and not bothering to prime the pump ( which was part of a TRF rebuilt short block from ~ 7 years prior ). Pressure on the gauge when cranking would reach ~75 psi. Anyway, upon firing up pressure was almost instantaneous ( 100 psi ). Regardless, for oil not to be everywhere after 90 seconds of running seems mighty peculiar to me :huh: It does makes sense that rockers and timing chain would be dry if the engine was switched off immediately upon registering oil pressure, however.

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That's what I did, having simply filled the spin-on filter 1st and not bothering to prime the pump ( which was part of a TRF rebuilt short block from ~ 7 years prior ). Pressure on the gauge when cranking would reach ~75 psi. Anyway, upon firing up pressure was almost instantaneous ( 100 psi ). Regardless, for oil not to be everywhere after 90 seconds of running seems mighty peculiar to me :huh: It does makes sense that rockers and timing chain would be dry if the engine was switched off immediately upon registering oil pressure, however.

 

That is the dilemma, it seems that no matter what the starting procedure was, if the motor has been running for 90 seconds and you still dont have oil getting to the head then there is something wrong. I havent seen anyone yet say hey, I had to crank it on the starter for 2 minutes before I built oil pressure..

 

So there is still something fishy going on here.

 

Stan

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That is the dilemma, it seems that no matter what the starting procedure was, if the motor has been running for 90 seconds and you still dont have oil getting to the head then there is something wrong. I havent seen anyone yet say hey, I had to crank it on the starter for 2 minutes before I built oil pressure..

 

So there is still something fishy going on here.

 

Stan

 

2 minutes and even longer is well known

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2 minutes and even longer is well known

 

Yes but that's at - what - 200rpm ? - Stan was running at 2,000.

Perhaps the rocker gear is so well made that it doesn't leak oil.

 

Sorry, it's not at all funny when you build something with infinite care expecting not to tear it down again for years if at all, and then find you're dismembering it after 90 seconds.

 

Ivor

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Yes but that's at - what - 200rpm ? - Stan was running at 2,000.

Perhaps the rocker gear is so well made that it doesn't leak oil.

 

Sorry, it's not at all funny when you build something with infinite care expecting not to tear it down again for years if at all, and then find you're dismembering it after 90 seconds.

 

Ivor

 

Hello Ivor

With the spark plugs out there is no load on the engine Stan said that he reduced the rpm down to 2000 think about it ?

Stan when you remove the cam which may not be nessasery post a pic i would also suggest you remove the sump and check main bearing's

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Why exactly are you all saying that an external oil feed line to the head is a bad thing? Curious. I am suspecting that you might be suggesting that this line will starve the oil to the crank.

 

I recently restarted my engine after replacing the cam (wiped out a GP2 cam), went with a TSIAutomotive S2 cam, did the oil prime thing with an electric drill (oil rained out of my roller rockers), show 80lbs of oil pressure at startup and 60 when warmed up and on the road. Should I be concerned about oil starvation on main bearings and how would you know.

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What did you read on the oil pressure gauge? You should have primed it with a drill, you can see the oil come up to the rockers while you do this. You should be able to do this now, and see oil come thru the hole at the top of the block that feeds the rockers thru the cylinder head. I had a machinist install cam bearings on a Datsun, bout 25 years ago and he didn't line up the holes in the bearing with the ones in the block. He was a drunk.

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What did you read on the oil pressure gauge? You should have primed it with a drill, you can see the oil come up to the rockers while you do this. You should be able to do this now, and see oil come thru the hole at the top of the block that feeds the rockers thru the cylinder head. I had a machinist install cam bearings on a Datsun, bout 25 years ago and he didn't line up the holes in the bearing with the ones in the block. He was a drunk.

 

 

Hey beer and high speed metal cutting machines. That is a great combination :-)

 

I just pulled the cam and dropped a wire down the hole in the block and it drops straight through the bearing as it should. So no problem there. The finger is further pointing at bad startup procedure and not a mechanical problem as I have run out of things to check.

 

Unless anyone can think of anything else I could be doing I'm inclined to put it back together and do over..

 

Stan

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Hello Stan,

 

I'm not sure how much stripping of the engine you have done, but my idea of driving the oil pump with a drill was not the usual one of priming the engine but of assessing where the problem lies without a lot of work. Remember that the oil gallery has access plugs along it's length so start at the pump and work along?

 

I would not be happy re starting it if I hadn't found the source of the problem.

 

By the way I don't believe all these tricks re priming the pump are necessary, just crank without the plugs until oil is circulating.

 

Alec

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Hello Stan,

 

I'm not sure how much stripping of the engine you have done, but my idea of driving the oil pump with a drill was not the usual one of priming the engine but of assessing where the problem lies without a lot of work. Remember that the oil gallery has access plugs along it's length so start at the pump and work along?

 

I would not be happy re starting it if I hadn't found the source of the problem.

 

By the way I don't believe all these tricks re priming the pump are necessary, just crank without the plugs until oil is circulating.

 

Alec

 

At this point the head is off, the cam is out so my plan is to make an adapter to spin the oil pump and see how much info I can get regarding where oil is going at each step of the assembly. One thing that I dont know is does the cam have to be spinning before oil can get through to the head ?. The book says the flats on the cam journal are there to slow down the flow so I'm inclinded to think that oil will route via the groove in the rear journal as long as the pump is pumping even if the engine is not rotating.

 

Stan

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It's a few years since I started my newly-rebuilt engine, but I remember many anxious seconds of cranking with no visible oil pressure. It was a minute or so, maybe two, cranking with no plugs in (I hadn't read the vaseline trick - the oil pump was simply gooped with assembly lube). The engine has run like a dream since. Well apart from my interfering with the CU setup that is!

 

Why not try cranking for a while with no plugs in? Presumably you applied assembly lube to the cam when you pulled & replaced it during this saga; In that case you're very unlikely to do any damage - there's precious little load on any bearings with the plugs out apart from *cam* bearings - and they are newly-lubed.

 

Cheers,

John

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Not sure whether this really helps or not but when i first started my engine after its rebuild I neglected to connect the oil pressure pipe to the gauge, causing oil to be dumped over my interior. You could try disconnecting this pipe and seeing if there is oil pressure at all.

 

Simon

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At this point the head is off, the cam is out so my plan is to make an adapter to spin the oil pump and see how much info I can get regarding where oil is going at each step of the assembly. One thing that I dont know is does the cam have to be spinning before oil can get through to the head ?. The book says the flats on the cam journal are there to slow down the flow so I'm inclinded to think that oil will route via the groove in the rear journal as long as the pump is pumping even if the engine is not rotating.

 

Stan

If you want to spin the pump with an electric drill, remember that you need a drill with a reverse gear,because the oilpump does only work in the anticlockwise dimension, and also that you need to old the adapter rod down, otherwise you will have oil all over the place when the pressure will push the rod out at once(if the rod has about the maximum possible diameter). Instead of a drill, turning the rod by hand is fast enough to get oil everywhere in less than a minute, from the moment you feel that the pump is working(i.e. with a mole grip on the rod)

I suppose the oil will pass to the head without any problem.

PS : oiling the distribution gears and chain when assembling the engine is often forgotten (how do I know).

PS2 : don't fill the oilpump with vaseline or any other non fluid substance : the pump will push the vaseline in the oil gallery, there the vaseline will make a block and prevent the pump from sucking oil because the pump has to make much more pressure now : for sucking the oil AND pusching the jelly blobs through the oilways. I don't pretend it will always go like this, but it will when bad luck is with you. The only thing you have to do is oiling the rotors : the pump will make pressure in seconds all time.

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Hi Stan.

 

Forgive me if ive missed this bit,but!!

As you say you have a spin on oil filter adaptor!,, do you also have connected to that an oil cooler?

Because there is apparently an oil spin on adaptor that will not work if no cooler pipes are attached!

It actually prevents the oil from being sucked up and into the filter, then out to the engine,as the blanking off bolts block it!

I bought one at an autojumble for £5 thinking ive got a bargain!! :P But luckily found out that it was this type before fitting it!! :(

Now I do I either invest in an oil cooler,or just leave it in my box of bits to sell off at Malvern! :unsure:

 

Dave

Edited by PILKIE
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If you want to spin the pump with an electric drill, remember that you need a drill with a reverse gear,because the oilpump does only work in the anticlockwise dimension, and also that you need to old the adapter rod down, otherwise you will have oil all over the place when the pressure will push the rod out at once(if the rod has about the maximum possible diameter). Instead of a drill, turning the rod by hand is fast enough to get oil everywhere in less than a minute, from the moment you feel that the pump is working(i.e. with a mole grip on the rod)

I suppose the oil will pass to the head without any problem.

PS : oiling the distribution gears and chain when assembling the engine is often forgotten (how do I know).

PS2 : don't fill the oilpump with vaseline or any other non fluid substance : the pump will push the vaseline in the oil gallery, there the vaseline will make a block and prevent the pump from sucking oil because the pump has to make much more pressure now : for sucking the oil AND pusching the jelly blobs through the oilways. I don't pretend it will always go like this, but it will when bad luck is with you. The only thing you have to do is oiling the rotors : the pump will make pressure in seconds all time.

 

Regarding:

 

Instead of a drill, turning the rod by hand is fast enough to get oil everywhere in less than a minute,

 

and

 

the pump will make pressure in seconds all time.

 

This is what puzzles me, this engine ran for 1 minute 30 seconds at 2000 rpm and we still did not see oil in the head. After we stopped the motor we pulled the bolt out of the oil gallery at the rear of the head and cranked the engine a few times on the starter, still no oil.

 

Other earlier comments suggest that 2 minutes to build pressure on the starter is not unusual.

 

This time around I'm going to err on the side of caution and not take the next assembly step until I see oil where it should be with the pump driven from the drill.

 

Stan

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