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Oil Pressure Oddness


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Not really, but I'm prepared to believe that the hydraulic gauge I plumbed in was giving me real info. I do think there's an internal problem somewhere and my money is on PRV or the pickup olive. Only way to find out is to open up the oil pump and sump to have a look see.

Not worth starting anything now...🍺

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Neil don’t talk to me about being paranoid about strange noises, a year or so ago I pulled up at a set of lights in the TE and seriously shat myself at this buzzing sound, it sounded catastrophic. I s

Ignition timing checked and carbs balanced and she's running like a dream. Smooth at tickover, pulls well, good oil pressure from cold (builds on the gauge in 5-6 seconds) and at hot tick over. T

Sorted mainly thanks to the help and advice on here (and over the phone!). Sometimes it's just what you need to give you the confidence to keep going 👍

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Started the strip down today. Dropped oil and water, carbs removed, auxiliary belts and alternator off. Now I'm down to releasing the cambelt tension and removing the auxiliary housing and sump to get to the bottom of this problem. Hopefully something obvious will be revealed so I can fix it and rebuild everything with some confidence...

I'm due a cambelt change after 3 years anyway, plus I had a noticeable whine developing which I'm now pretty sure is the alternator as there's a slight clicky roughness to the bearing when I spin it by hand. So at least that'll be fixed as part of the process.

One thing I do need to have done is the valve clearances and cam oil seals. I'm shying away from doing that myself due purely to lack of confidence and potential for (expensive) cock up. Should I be? Or is it something I should just get into whilst the belt is off? How difficult a job is it for someone reasonably confident with spanners but who's never done valve shims before??

Not worth starting anything now...🍺

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If you're confident with a feeler gauge and grab a cheap micrometer to measure the shims, the valves aren't especially difficult, they just take a lot of time. Take care to use magnets to keep them from escaping when you pull the cam carriers, and have a 16 space container to set the buckets and shims in as you pull it apart. There's a spreadsheet out there that takes care of the math for you. Just be prepared to measure, assemble and reassemble several times as it never seems to be perfect the first time. And use a torque wrench for the cam carrier bolts as they tend to strip out easily. 

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Apologies, I haven't read the workshop manual on this yet, but when you say assemble and reassemble do you mean assemble back onto the engine or 'test on the bench'?

Sounds frustrating!?

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You need to take the cam carriers on & off to 'dry fit' the shims and verify the measurements. It takes a few tries.

 

Tedious but not difficult.

 

Atwell Haines

'88 Esprit

Succasunna, NJ USA

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Stripped off the sump and auxiliary housing today. The only visible problem I found was the strainer in the sump has fallen off the pickup and was sitting in the base of the sump. Not ideal and I'll replace it but not sure it would be causing my problem?

Pickup pipe olive looks OK apart from a tiny crack on one side. I'll replace it anyway.

The PRV seems fine, definitely not stuck open and strong spring. Washed it through with some carb cleaner just to make sure it's clear.

The oil pump itself looks fine and the shaft spins freely. Could it still be worn? Just not sure why I would have good pressure when running if it was?

I was hoping to find something obvious so a little disappointed. Ideas anyone??

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In the next phase of 'things to do while the cambelt is off' I checked the valve clearances today.

For the inlets they're all measuring consistently at 0.003", which is nice, but out of the spec 0.005-0.007 so it looks like they'll need re shimming. Is it normal that these should close up rather than the clearances getting bigger through wear??

On the exhaust side things are better, with measurements of between 0.010 and 0.012 for 7 of the 8 valves vs a spec of 0.010-0.012. Just one is at 0.008. Almost good enough to leave if the front cam oil seal wasn't leaking on that tower ☹️

Its the first time I've measured these and I've no reason to believe they've been done before so do those clearances seem as expected for an 85k N/A engine?

Access to the cam tower bolts is OK but restricted with the engine in. Is there much risk of any threads stripping out on reassembly and torqueing or are the torque figures low enough that it's not likely to be an issue?

Not worth starting anything now...🍺

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Yes normal,  Can down to carbon build up or valve springs or maybe the bottom of the followers or slight cam lobe wear  :)   Not much in it as you say so nothing to worry about, just re shim :)

Regarding cam tower bolts stripping there is always the risk,  cant remember the torque settings of memory, but be very gentle with them,  iirc i think i just did them by feel :P

A

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By feel sounds good to me. 'Tight enough' will be tight enough...

Just ordered £500 of bits from SJ and PNM to do oil pump/pickup, cambelt and valve clearances. Only problem is there's a 2-3 week wait for the pickup pipe.

I plan to get the sump and oil pump back together before tackling the valve clearances in an effort not to have too many things in bits  on the bench at once! I'll have to order the necessary shims once the cam towers are off and I can measure the existing shims.

Unless anyone local (Hants) has a box of shims I could 'shop' from?

Not worth starting anything now...🍺

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  • 1 month later...

Slow progress on this due to a holiday and (still) waiting for parts from SJ.

I now have what feels like every gasket, olive and and O ring associated with building and maintaining oil pressure as well as the new pump inner and outer annulus thingies. The only thing I'm waiting for now is the new pickup pipe & strainer for the sump which SJ promised me 2 weeks ago but is still 'being made'...

I'm hoping to get this side of things back together over Christmas hols before moving onto the valve shims, then finally new cambelt on and hopefully back on the road.

In the meantime I forced myself into the cold garage last weekend to clean up all of the mating surfaces ready for reassembly. Today I removed the crank aux pulley to liberate the cambelt tensioner and press on another new bearing. The SKF one, new from SJ just 3 years ago has only done a few thousand miles and is totally shot . This time I shopped at PNM but it's the same SKF bearing. Hopefully it'll be better...

Just hoping that pipe turns up from SJ then I can get on over the Christmas break.

Not worth starting anything now...🍺

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Today’s problem... the head of one of the torx bolts holding down the inlet cam tower rounded off whilst trying to undo it 😡

Any suggestions on how to get it out?? Not much meat on the head to start with and they're ferkin tight.

@peteyg, @Chillidoggy, @Barrykearley ever had this happen?

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Not worth starting anything now...🍺

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Sorry Neil. No silly torx bolts on an S2. Just good old fashioned hex heads. Can you weld a nut on there maybe or make a channel with the dremmel you can get a hefty screwdriver into?

Pete '79 S2

LEW Miss September 2009

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They're damned tight to crack off so I doubt a screwdriver would shift it, even if I could get a slot in the head.  I don't have a welder so that option's out too ☹️

I tried hammering a smaller socket onto it but without success the first time. Having a break now to repaint the cam covers then I'll revisit it later and decide what to do. Maybe I'll just leave the valve clearances as they are...

Not worth starting anything now...🍺

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Thanks @Sparky. I looked at those but the stub that's left is only about 7mm (and short) and these only go down to 8. I know this because I tried hammering a 7mm socket onto it and it just slips round... 

The head is soft too because I tried carefully tapping it round with a punch and it just carved away a piece of the head.

Theyre so bloody tight to crack off I don't why they used torx heads?

Not worth starting anything now...🍺

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Possibly try using a small sharp chisel, or punch,  on the flange to drift to start?  Last time I looked, Lotus charged a tenner a piece for those bolts.   Thread will be gunked up with anaerobic sealant.    

Ah - just seen you have already tried....

 

Edited by 910Esprit
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Chisel just carves a piece off. The head seems unusually soft given how much force they need to crack off and how small the bolt (and teeth of the torx) are.

Now I think I'm down to the weld a nut on option... After that I'm out of ideas other than drill the head off 🤔

Not worth starting anything now...🍺

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Oooof!

I was going to suggest the same as Sparky, but if the remaining head is too small, then perhaps these will do the job? They definitely go down to maybe 4 or 5mm and up to 8mm and they’re 1/4” hex drive. I bought them from Sears to remove damaged screws, Craftsman made, not sure if they’re available in the UK, though. If it were me, I’d avoid chiselling or grinding until all else fails.

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Margate Exotics.

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3 hours ago, eeyoreish said:

They're damned tight to crack off so I doubt a screwdriver would shift it, even if I could get a slot in the head.  I don't have a welder so that option's out too ☹️

I tried hammering a smaller socket onto it but without success the first time. Having a break now to repaint the cam covers then I'll revisit it later and decide what to do. Maybe I'll just leave the valve clearances as they are...

Impact driver?

Pete '79 S2

LEW Miss September 2009

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Finally got the better of it. In the end I managed to drill the head off in situ. Just lucky it was one of the top ones because if it had been one of the studs accessed through the brass caps or on the exhaust cam housing I'd have been totally knackered for access.

With the tower lifted off the remaining stud wound out easily. Neil 1, Esprit 0 after extra time...

Tomorrow I can now start stripping the cam out and replacing the seals etc.

I think the exhaust cam, where all but one of the valves is within tolerance, will be staying where it is this time around. Risk vs reward and all that...

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Not worth starting anything now...🍺

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Wow, that head must have been really buggered, as the 8mm has removed every damaged one I've ever done.

British Ambassador to Florida, New York, Denmark and Newfoundland.  And Sweden.

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4 hours ago, Chillidoggy said:

Oooof!

I was going to suggest the same as Sparky, but if the remaining head is too small, then perhaps these will do the job? They definitely go down to maybe 4 or 5mm and up to 8mm and they’re 1/4” hex drive. I bought them from Sears to remove damaged screws, Craftsman made, not sure if they’re available in the UK, though. If it were me, I’d avoid chiselling or grinding until all else fails.

 

The ones shown by Sparky are made by Irwin, they do additional sets, which are imperial sizes, they also do the smaller type in the post by @Chillidoggy  . There are other brands available here in the UK but I've not tried those.

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