Oil Surge

My 1600 t2 engine in my bay window camper, suffered from the oil light coming on whilst negotiating mini roundabouts near my house. I have checked the oil level and it is at the full mark. Does this mean I need to go for a deep sump, (I could slow down, but there are too many school run range rovers trying to run me off the road) or is there anything else I should try? The oil has been changed a couple of times, and there are no other problems with the engine.

 

Oil pressure sensor needs replacing?

 

Unless you are cornering so fast it feels like your bus is going to roll over it shouldnt be possible for the light to come on with the oil running up into the cylinder heads.
This leaves faults.

Most likely is something silly :

1. Sender is faulty. Try another one.
   
2. Sender wire is shorting as it waves around.. burnt insulation off on touching heat riser pipe nearby ?
   
3. Save my bug dipstick switch is closing.. this is an aftermarket fixture that flashes the oil light when the oil on a bus is just warming up around 90 degrees C.. Its set for a bug. For a bus somewhere between 100 and 110 degrees C is a concern.
4. Driving style : letting engine revs drop below 2000 rpm under load, maybe change down another gear ...
   
5. Engine hot - your engine is on the verge of getting overheated and the oil has thinned to the point the pressure is falling for real at low RPM. For this its usually an air leak in the inlet manifold between the carburettor and cylinder heads. This is then most common cause of overheating . And it can mean new engine if not fixed. Alternatively wrong timing can also heat up an engine.

Below this are more serious ideas where to fix involves mechanical work..

1. Loose pickup pipe - air can get in to the oil pump inlet if an engine builder knocked it.
2. Worn oil pump
3. Worn bearings.. fill up with thicker oil, start saving for an engine rebuild in a year or so..
   
4. Oil pump drive dog slipping on camshaft. Wear on the oil pump shaft and or the bearings on the camshaft are worn. Could be wrong pump installed by an engine builder.. different camshafts need more or less oil pump driveshaft protrusion.

 

It’s pretty new, maybe a month old. The old one was a taper fit, so I got the proper one with the copper washer.

 

eeeeek, I’ll take the filter strainer out next oil change and see what i can see. It has a oil pump screw on filter conversion, I had better check that too, I have a new filter ready to go on. I noticed you can buy a deep filter bowl, to stop “oil surge” but they are £60 which is as dear as a deep sump.......

 

Did you also have the problem before you changed the switch?

 

The “proper” one is the one with the taper

 

Yes I’m pretty sure I did. It’s just now the weather has warmed up slightly I’m using it more.

Also the old taper oil switch was weeping all the time, and I was very wary of overtightening and cracking the block. The new one is spot on for leaking.

 

How much oil are you putting in at the oil change? The dipstick might not be marked correctly and if you’re not putting enough in…

 

Now you mention it has an added oil filter, can you show us pictures of how it is plumbed into the engine block .
Some installations might have associated potential problems , some oil pumps with oil take off covers can leak air between the pump and engine block.. or produce low pressure ...like my CB Maxi 3 where putting the gasket on upside down causes an internal leak.

One possible error is to get the oil flow the wrong way through a full flow filter so it collapses and blocks the oil flow.

Done right a full flow filter is a good thing as your engine will have much less metal circuating.

It might also be installed with a larger capacity engine then the overheating may be down to needing an oil cooler in the external circuit as well as the doghouse cooler..

 

I have just finished a couple of quick welding jobs, hopefully the last. So I’ll get photos in the morning if that’s ok? It did seem like it didn’t take very much, so I’ll do an oil change and measure it out. I have a Haynes manual so will check the capacity. I will check the level again now it’s in the garage in case it’s a bit low, but it was fine yesterday and it doesn’t leak that much.

The oil filter adaptor is the cast type that replaces the oil pump cover and points left as you look at the engine. I’ll eat photos anyway tomorrow cheers...

 

Ok, checked the oil level, and it’s only on 1/4 above minimum, which may be the problem, I must have checked it on a bit of a slope last time.

There are the photos of the type of oil filter it has. I have a shorter screw on filter to go on it as I got one that was too long last time. I’ll do an oil change and check it’s getting the correct amount.

 

Low oil level is the problem.
Tony

 

There’s no need for a deep sump in any case is there?

 

No.

 

There was a big thread on thesamba.com about those combined filter/pumps causing a restriction in the supply to the pump. They also put the filter in the direct hot air path from the air thats passed over the cylinder heads warming it up. That said all mexican beetles use that kind of pump/filter and they seem to last.

 

And remember that what you need to do is fill the engine with the total volume of oil you need including filter and hoses.
Which is not in the book!

For instance, my setup uses 3.5 litres of oil being the stock setup plus a filter, a loop of 3 metres of hose and an oil cooler.

The easiest way is to say put in 3 litres, take out the plugs, turn over on starter until the oil pressure light goes out, top up oil to the mark and then replace plugs, start the engine , stop it , wait , and then adjust the oil level.
If its too high you can use a suction pump on the end of the dipstick instead of trying to drain out a bit by undoing nuts underneath.

Then write down how much oil it took and next time just put that much in.

The turning over the engine bit until oil light goes off is mostly to avoid running at zero pressure. I often get lazy and just pull the wire off the coil negative to disable the ignition.

Unlike a modern car, putting even a litre too much oil in will not kill it even if it spits oily spray around , as there is no platinum catalyst to coat with oil.

 

Oil changed, 2.5l brought it just below full on the dipstick, but now it’s run it will need a topup after filling the filter.
I went round the block and no sign of an oil light. Also I straightened out the drain plug plate, as it was leaking. All the seal washers were steel, so replaced them with the copper ones that came in the kit. Also changed the gearbox oil while I was under there.