Loss of Oil Pressure on Right Turns

[Galwaylotus]

At the risk of ploughing old ground . . .
I am experiencing a loss of oil pressure on right-hand (roundabout) turns. If I just tiptoe around it's fine but otherwise I can see the gauge needle drop. I checked the oil level after a drive this morning and it was perhaps 3-5mm below the full mark. On left turns there is no problem. I know there are baffle systems designed for the sump but am just wondering if this is typical on standard sump Twinks.

[paddy]

I think it's typical if there's not enough oil in. When it happens to me the symptoms are the same, and it's a reminder to top up the oil.

I think your dipstick tube is set at the wrong level, or you have the wrong dipstick.

You can baffle the sump and there are ingenious designs with flaps and shutters, but I think people rarely go to the effort for a road car. There shouldn't be a problem just going round a roundabout at road speeds.

Paddy

[types26/36]

I am experiencing a loss of oil pressure on right-hand (roundabout) turns. I know there are baffle systems designed for the sump but am just wondering if this is typical on standard sump Twinks.

http://www.gglotus.org/ggtech/tc-oilstu ... lscave.htm

http://www.gglotus.org/ggtech/tc-oilpan/baffledpan.htm

[neilsjuke]

I would do a oil change and measure the oil then check the level on the dip stick could be wrong stick or the tube in the water pump cover is to far in.

[rgh0]

You can experience oil pressure loss on the road in RH turns due to the offset design of the pump pickup but it is rare in day to day use and most people dont worry about it. I would check the oil level after a fresh fill with the correct quantity ( I assume you have a standard sump) and adjust the dip stick if needed so you can keep the level correct. You can safely fill around 5 to 10 mm above the normal high mark to help reduce the problem if it still persists.

One of the common reasons for sensitivity to oil pressure loss is worn cam bearings and to much oil staying up in the head and not in the sump. It may be worth a check of the cam bearings and a replacement if needed, also potentially the cam bearing tunnels may need a line bore if misalignment is the source of the cam bearing wear. People put a restrictor in the head to limit oil flow but this is really just a bodge to cover up the worn bearing problem.

cheers
Rohan

[Galwaylotus]

Thanks, guys. Plenty to look at. I've used Shell Helix Plus semi-synthetic oil but recent postings seem to indicate a classic 20W-40 is preferrable due to low ZDDP levels in modern oils so I'm sourcing some and will probably do an oil change then. (Only a couple hundred miles on the current oil but it's a year plus old so I'll change it.) I'll carefully measure the amount in the refill and check the dipstick then to see whether it's accurate. My hot oil pressure is about 50 psig so I don't believe I have excessive bearing wear - and that's with a 10W-40 semi-synthetic oil. I'll post my findings when I have it sorted. Thanks again for the quick responses.

[freddy22112211]

Either my car is different or I drive faster than most (unlikely) - I had no choice but to fit a baffled sump as I always had this problem, even when full, (level checked with correct amount of oil on oil change). One of the last Elans made.
Gordon

[stugilmour]

This article and ebook might be of interest

http://www.elantrikbits.com/baffle.html

[rgh0]

Thanks, guys. Plenty to look at. I've used Shell Helix Plus semi-synthetic oil but recent postings seem to indicate a classic 20W-40 is preferrable due to low ZDDP levels in modern oils so I'm sourcing some and will probably do an oil change then. (Only a couple hundred miles on the current oil but it's a year plus old so I'll change it.) I'll carefully measure the amount in the refill and check the dipstick then to see whether it's accurate. My hot oil pressure is about 50 psig so I don't believe I have excessive bearing wear - and that's with a 10W-40 semi-synthetic oil. I'll post my findings when I have it sorted. Thanks again for the quick responses.

Worn cam bearings resulting in to much oil in the head will not necessarily affect oil pressure if the rest of main and big end bearings are OK. I often see worn cam bearings in engines that have new bottom end bearings as the cam bearings are expensive and people tend to not put in new ones with rebuilds if they can avoid it.

If after checking the level you still have problems with loss of pressure going relatviely gently around round abouts I would investigate this as a potential source of the problem. If you are loosing pressure when taking the car through a roundabout in your normal driving style and this style is close to ten tenths and on the limit then you really need to baffle the sump regardless off the bearng conditon.


chers
Rohan

[john.p.clegg]

If i was you,just as an exercise, I'd replace the oil sender with a low pressure switch ( temporary ) wired to a big red light on the dashboard,this isn't dampened and is guaranteed to scare you...

John

[neilsjuke]

My thinking on oil is Millers classic 20/50 for first 2000 miles to bed in then Valvolene VR1 Racing oil SAE 20/50 when you want to give it some stick
Neil

[Galwaylotus]

If i was you,just as an exercise, I'd replace the oil sender with a low pressure switch ( temporary ) wired to a big red light on the dashboard,this isn't dampened and is guaranteed to scare you...

John

There's not much damping in the gauge as is and a dropping oil pressure needle gives me all the fright I need, thank you. No red light required!!

[ceejay]

Hi Guys.
This is an interesting thread, I put up with the "oil pressure loss on right hand corners syndrome"
for nigh on twenty years. It made little difference whether I overfilled the sump or not.... normal
driving was OK. I also measured the dipstick tube height and all was OK.
(Question: What is normal driving in an elan??) Should I ask Jay Leno... just kidding.

The next step was to investigate a sump baffle..... I spoke first to vintage racers at various historic
meetings, I spoke to Rohan at length about his system, looked at photos he had sent... then
wondered for ages about how I would approach the problem.

About two years passed before I decided to bite the bullet, I stripped the old sump off the engine
and began the task of building a gated sump baffle, the elan was of the road for about nine days
while doing the project.

So does it work? Absolutely, it is one of the best mods I have done to my elan, now
I don't have to worry about watching the oil pressure gauge when driving ten tenths
around corners... in fact I have never enjoyed hard tight corners more since installing
the sump baffle.... Now I find any tight corner as sheer driving enjoyment... just what
the elan was designed for.... if only lotus had got the elan sump baffling system right
from the out set, we would not be discussing how to cure the problem.

There would be a few elan owners wondering how hard it is to fabricate a sump baffle:
Not that difficult, if you are good at sheet metal fabricating, know what you are doing,
and you have good mechanical skills... if you are ham fisted with tools then take it to
someone else to do for you. But that could cost you money!

How much does it cost then? Not much, the material for mine cost about $20.00, no
BS. Amazing how such a simple and low cost device can be so effective.

The result of all this work is clearly documented & illustrated in the the ebook
"How To Build A Sump Baffle" which is available for just a few bucks at our web
site.

There are two options with this problem.

Do nothing, just keep the sump overfilled and hope like hell that you don't
end up blowing the engine bearings in your twink.

Do something positive and build, or have someone build for you a gated
sump baffle, and forget about oil pressure loss on right hand corners forever!
It's a no brainer!
Col.
http://www.elantrikbits.com/baffle.html

[Galwaylotus]

In my Mini, I had a similar problem whenever the oil level dropped a bit. When the engine/gearbox was out for other work, I had a central oil pickup installed and I've never had a drop in pressure since. Where is the oil pickup on the Twink? I assume it's offset to the right or the problem would occur on both right and left corners. Has anyone developed or tried a central pickup?

[ceejay]

A central oil pick-up point is all part of the sump baffle fabrication system.
Col