Oil Pressure Warning Lamp


Hello. I recently performed the 3,000 mile oil and oil filter change on my F70 1990 Non-Turbo 'trak. Since then the oil pressure warning lamp stays on for about 10-15 seconds when I start up after sitting for a day+. Whereas before it went off in under 5 seconds. I used the same filter and mineral oil as previous oil changes. After I refilled the engine with oil I checked under the truck and discovered the bung was leaking, so I had to drain the new oil out and fix the bung. I didn't have a clean container to put this in so I used another 5 litres of brand new oil. As a result the oil in the engine is still clear and clean after about 200 miles. I wonder if this "flushing out" with new oil has cause the low pressure at start up due to clearing worn clearances previously blocked by sludge ect.

Any thoughts?


Oily Light


I recenty had the same problem with a leaking sump plug and did as you did, dumped the recently replaced oil and refilled with new oil but did not replace the as new filter. I noticed no change in the time the oil pressure light took to go off. I use a semi syntetic oil, and it did not stay "clean", as I checked the level the day after the oil change.

Edward (ews)

Edward (ews) '92 Fourtrak 2.8 TDX

Thanks for your reply. It

Thanks for your reply. It looks like there is something else going on, possibly the valve in the filter...

Can anyone else offer any ideas?


Non return valves are fitted

Non return valves are fitted to most engines, some in the oil filter, others in the cylinder head or oil galleries, obviously these are to stop the oil returning to the sump. When the engine starts it builds up oil pressure much quicker if it does not have to fill the oil filter and the oil galleries, so most are fitted in the filter.

Some cheap aftermarket filters do not have these fitted, even though they should, consequently they sell as they are cheap, but people find these sorts of problems with them.

Firstly i would replace the filter, if the engine is OK it isthe filter's non return valve is defective, or non existant. If its defective it needs returning to the supplier to they can remedythis faulty filter by reimbursing its costs, the supplier will then contact the manufacturer. manufacturers can then check their production processes for a faulty manufacturing process.

Suppliers have catalogues which supply considerable filter data, this will include if the filter has a non return valve fitted, if it does not show this, then here is the problem, avoid this make of filter and post on this site.

I thought it could be the

I thought it could be the non-return valve. The filter is a motaquip I think. I don't think it would be the engine, as it happened only after the oil and filter change. Do you have a DL-42 engine Assassin? If so what filter do you buy?

Thanks for your reply!


Fourtrak 2.8 TDX, F75 DL-52 engine


I buy my filters from 'Milners' ( Top of page 'Parts Dealers') A'Filter Kit' and change them all at the same time, good price as well. I also, at one time was supplied with a 'Motaquip' oil filter from a local motor factors, but decided not to fit it, as it was much shorter than my usual filters supplied by 'Milners'.

Milners can supply new sump plugs and washers.

Edward (ews)

Edward (ews) '92 Fourtrak 2.8 TDX

My daihatsu is an F20 fitted

My daihatsu is an F20 fitted with a now supercharged GMC V8 diesel fitted, so these filters would not fit them.

I use Milners for filter kits for most japanese vehicles, including the multitude of Fourtraks on which i still work or modify. Only ever had one problem with Milners, this was with an exhaust section, they sent a van out the same day with a replacement, and collected the wrongly supplied component.


Is there pictures of that beast on the site? I checked though about 10 pages, but couldn't see anything like it. If they are on here what section and page, and if not post some!(please).

No pictures on the site, i

No pictures on the site, i have even been approached by a cou le of magazines but refused, it was simply an exercise in my engineering ability put into one vehicle.

Many people have similar high end engineering qualifications as i do, but very few can translate this into a working item. This was purely a personal thing to satisfy myself that i still had the theoretical skills, but could still translate them.

Motaquip do not manufacture

Motaquip do not manufacture filters, they are simply retailers who do what so many others do, they buy the cheapest and have them branded as their own.

These are often made in countries such as China, Malaysia, or Korea; and are often copies of the original equipment, and cheap copies.