Oil light on when hot idling

[T25rc]

Ok,

Oil changed - a 6 mile run with some good hills and the oil light is still coming on at idle. However it is only at low idle (which currently means when the headlights are on and indicators, but it probably shouldn't dip so much with power useage!)

I pulled the dipstick and grabbed it - i could probably hold it for a half second on the first go.... Not sure just how hot an overheating one would feel.

I think i'm going to have to look over how the aircooleds are actually cooled - i'm a vw watercooled minded person (mk2 golfs!) and wasn't aware of flaps etc affecting things.

[kevtherev]

Some very good information here from Brett-Air cooled

2 litre CU

timing 5 degrees after TDC with vac hoses on and idle stabiliser disconnected and plugged together this is at 850 rpm manual 950 on an auto,
alternatively disconnect the vacum on the retard side on the dizzy and set to 7.5 degrees after TDC at same RPMs,( on the CU there is 11 - 13 degrees of retard at idle)
whilst tiking over pull the advance vacum pipe off the dizzy and check for vacum, there should NOT be any if there is then the carbs are set up wrong, try the other carb if none then use that one instead but this wont totally fix it, youll still need to adjust the throttle plate on the bad carb.
Balance the carbs using a snail balancer do this at 2000 rpm then 1600 then 1200 or something like that
disconnect both pipes from the dizzy and plug the hoses with something
rev the engine to 1600 rpm timong scould be 21 degrees
rev the engine to 3400 rpm timing should be 32 degrees

I have been scratching my head for over a year and it still dont run right and uses troo much fuel,

poor timing and a weak mixture will cause overheating.
Have you looked in the wiki and read the reams of info about tinware and cooling on Aircooled engines?

It's quite simple once you start to understand it.
Simply put....there's a hot side and a cool side to the engine, and a fan to move cool air over a hot engine, that's why the two halves must be separated by tin.

[T25rc]

Ok, a very annoying update.

I had reset the carbs to proper settings, done the mixture, reset the tappets, set the timing up right and the camper was running MUCH better than since i've had it. It was about half as loud, and twice as torquey. The oil light was only coming on at idle when it had been running for a good while (which according to haynes (book of lies?)) can be normal on one of these engines when old.

So, i went on my first camping trip to cornwall (70 miles trip).

The engine got progressively less powerful after roughly the first 20 miles, until it was not very good to drive again by the time we arrived and louder again.

Before the journey home i checked the oil, which was still above the 'low' mark by about 25% between the 'high' line - and i had none spare, so i thought i'd get it home. It was much of the same from the off, its very slow and loud and the oil light has started coming on even when running for only about 5 mins.

I've topped up the oil to the max line, and gave it a very short drive. It seems very slightly better - however the oil light still came on very quickly.

Does it sound like the engine is goosed, or is there some more things to try? (strainer? Oil pump (is that easy?) )

Thanks for any help, it's very annoying since it was runnning so well and now its basically unusable for the summer again.

[sarran1955]

Hello,

You seem to have done all the right things so far.

You need to check your oil pressure, both at idle and under load.

I have a op gauge with 2 metres of hose. This means you can have someone look at the gauge when you test drive.

You'll find the requires pressures in Haynes or on here.

If your pressure really is too low, then you may well be looking at an engine rebuild, or getting at least a known good block and rods.

Cordialement,

[fullsunian]

Ok, a very annoying update.

I had reset the carbs to proper settings, done the mixture, reset the tappets, set the timing up right and the camper was running MUCH better than since i've had it. It was about half as loud, and twice as torquey. The oil light was only coming on at idle when it had been running for a good while (which according to haynes (book of lies?)) can be normal on one of these engines when old.

So, i went on my first camping trip to cornwall (70 miles trip).

The engine got progressively less powerful after roughly the first 20 miles, until it was not very good to drive again by the time we arrived and louder again.

Before the journey home i checked the oil, which was still above the 'low' mark by about 25% between the 'high' line - and i had none spare, so i thought i'd get it home. It was much of the same from the off, its very slow and loud and the oil light has started coming on even when running for only about 5 mins.

I've topped up the oil to the max line, and gave it a very short drive. It seems very slightly better - however the oil light still came on very quickly.

Does it sound like the engine is goosed, or is there some more things to try? (strainer? Oil pump (is that easy?) )

Thanks for any help, it's very annoying since it was runnning so well and now its basically unusable for the summer again.

So when you set the timing and carbs, what have you set the tickover to? As somebody else mentioned it should be 900ish, any lower and the oil pressure lamp could well come on. The worrying thing for me is you say it gets noiser, do you mean it rattles or could even be pinking?

[California Dreamin]

I'm afraid we are all just guessing until you actually check the oil pressure with a gauge.
The fact that it gets noisier isn't a good sign I'm afraid.
An oil cooler might be a good addition in the future.

Martin

[T25rc]

Cheers,

I will have to get an oil pressure check done in the next couple of days.

I had it running for a little longer today, at the start the oil pressure light came on - however after about 10 mins+ running it seems to have gone out for now (i didn't run it until hot, so it may have re-appeared).

It is still very noisey though, it seems like its coming from the rocker covers indicating tappets? - would they be last to get oil if it was low pressure? I'm running 20/50 mineral.

Would running the oil low(ish) on the long run have starved them, and now they are still not refilling?

Here's a video of how it was running tonight. The close up gives a slightly skewed sense of how loud the higher pitched noise is, the other deeper one seems like 'normal' engine noise. Anyone want to guess the Idle, too high or low?

http://www.youtube.com/watch?v=gNjt5SYiZbA" onclick="window.open(this.href);return false;

[sarran1955]

Hello,

Idle is too low.

Try changing oil pressure switch.

Get oil pressure checked, as per above.

Cordialement,