Low Oil Pressure on GTI Conversion

Post by **mart1971** » 17 Sep 2007, 22:13

Hi All,
So far you have been a wealth of knowledge.

As you may know from a previous post of mine, I am new to the T25 schene and didnt even realise that my T25 had been converted to a GTI engine until I posted a question on here, despite having some reasonable mechanical knowledge yet very little T25 knowledge.

My Golf GTI engine suffers with Low oil pressure when the engine has not started for a few days or if descending down a steep hill.

This would suggest a problem with the oil pick up.
I have read throught the conversion pages, but can not find any reference to whether the oil pick up has to be modified when the T25 Diesel Sump is fitted to the GTI engine.

Has anyone had any experience of this. It is as though the oil is draining back and can take as long as 20 secs for the oil light to stop flashing after the vehicle has stood for more than 24 hours. It is very worrying and just as I am about to shut it off, the light goes out and that engine goes very smooth and quiet so I know the pressure is not there.

Post by **HarryMann** » 18 Sep 2007, 07:44

Longer/angled Diesel pickup needs to be on the pump if the Gti is installed with the JX 50 deg. canted over parts.

Several possibilities for drain back. Chnage the oil and filter (to a genuine VW) might help.

Others will have better information soon I hope...

Post by **big red bus** » 18 Sep 2007, 17:56

I guess the golf gti engine is an 8 valve PB engine. In my experince with golfs these engine suffer with oil pressure problems when they get a few miles on them. Had this problem with my golf. Must use a genuine filter and good quality oil, not sure about pick up modification but might be an idea to replace oil pump and pressure switches (simple job on these and quite cheap). Start there the rest just gets more expensive.

Post by **HOT 1200** » 19 Sep 2007, 13:51

If it helps, I had the same problem on my 1.9TDI conversion....
(Pick up/etc all changed over to the correct spec)

It baffled me for a while, I had the correct T25 pick up, sump and all the right bits, yet cold starting in the morning took 10 seconds or so before the oil light would go out and you could here the engine was not happy.....
The oil filter was a 'Halfords' own brand part.......In desperation I changed it for the corrrect MANN filter........
The problem went away instantly.......

That said.....If the van is left for a few days, the hydralic lifters rattle for the first 3-5 seconds......I have put this down to two theorys.....
1. The engine has 106,000 miles under its belt, the lifters probley need changing.....?
2. I wonder if the hydrolic lifters have trouble holding the their priming oil due to being laid over at 50deg.......?

Either way, its now done well over 10,000 since the conversion...no problems so far......

Do GTI PB engines have hydrolic lifters.....????

GaV

Post by **toomanytoys** » 19 Sep 2007, 15:32

Have to agree about filter and oil... Use a "MANN" filter... (GSF do them) and prob 15w40 oil...

Lifters.. could be the oil is a little thin.. or like you say.. coz its leant over and its got a few miles on it..

Post by **HarryMann** » 19 Sep 2007, 21:11

My AAZ takes about 3 seconds for the light to go out and a bit of top-end rattling to stop... doubt if it's being lent over that's the problem though.

Worn idler shaft bearings might contribute to your Gti pressure problem

Post by **mart1971** » 30 Sep 2007, 08:14

Hi All,
Thanks for the replies.
I have changed to Oil and filter to a Mann type from GSF.
It appears there may be more to this.
Oil pressure on start up is OK when used daily, but I drove 140 miles the other day to Devon and as I was running late, I pushed her harder than normal and sat at round 70mph all the way. The engine did not get hot at all but as I cam off the motorway at Jnct 30, the oil light came on and I could here the engine noise raise slightly. I dropped the revvs and pulled over and after about 10 secs the oil light went out. This was very worrying so I pulled up at the nearest place and checked the oil levels. The engine had used a good 2 litres of oil over the 140 miles. No signs of any leaks anywhere and no drips. I topped her up and drove to the campsite. I prepared myself for major problems so I drove home very carefully at 55mph. When I got home I checked the oil levels again and driving at this speed, the oil level had hardly dropped. I whipped out a spark plug and there are signs that she has been burning some oil. What is wierd is that there are no signs of oil burning in the exhaust gasses.

Has anyone come across this before ? Could revving the engine for long periods of time, be an early sign of bore wear ?

Also, has anyone got any pictures of the diesel oil pick up which I hope has been fitted to this petrol engine so I can take the sump off and compare to what is on this one.

The conversion had been done before I bought this van, and it does have a T25 sump, but I do wonder if the pickup is correct for this sump / engine angle.

Many Thanks
Martin

Post by **HarryMann** » 30 Sep 2007, 23:51

Could revving the engine for long periods of time, be an early sign of bore wear ?

Not makey sense that...

I suspect overfilling is culprit to some extent...

Oil getting stirred up by crank and pumping, froths a bit, lowers oil pressure, alos more gets thrown up bores and past rings...

Until a correct and good oil level is obtained, few conclusions can be drawn... Possibly also getting overhot under high power like it does in diesels. Exact same symptons.

Post by **HOT 1200** » 01 Oct 2007, 15:32

are you sure its got the correctly modified dipstick....
A standard Golf dipstick does not work....if using the standard dipsick, you will of put too much oil in the engine to reach the MAX mark (by over a litre !!!)

With a new filter and oil drained out......Fill with exaclty 4.5 ltrs of oil.

Even with 4.5 ltrs, it wont even reach the MIN mark on the Golf dipstick, fooling you into adding even more oil.........and causing all sorts of problems.......

GaV