Oil Pressure

M

Mark LaBarre

New member
I ran a drivers school this weekend to shake out the car before the race the next day. Engine ran fine for the 4 sesions I was out there. The next morning, the oil cooler (not the stock one) blew apart. So I removed it and ran the practice and qualifying sesions with no problems. On the way to the grid for the race, either the oil filter or housing let loose (havent looked close yet), didn't know it till after the pace lap. In the rush to get to the track, the oil pressure gauge was not installed . Before I dig into this (still tired from the trip) anybody have any problems with over pressurization before ?
 
One my GP engines, which I setup fairly tight (.0015-.002" on the mains, .0025-.003" on the rods), I see 125 psi at startup @ 2000 RPM. I'm very careful not to rev the motor past that until I see some temperature in the engine. Once the motor heats up to 190F water, 210F oil, I'll see 30-40 psi at idle (1200 rpm) and 70-75 psi (measured at the head) @ 7000 rpm. The pressure at the bearings is about 10 psi higher than at the head. This is with a stock 1.6 VW pump, not one the later high output pumps.

I'm sure some folks have fiddled with the pressure relief spring in the oil pump to relieve some of the pressure going to the bearings, but that's not strictly legal.

Filters: I stay away from the FRAM filters, and strictly use the Mann filters from Germany. I have a filter cutter, and the metal is thicker on the Mann filters than the aftermarket filters (Fram, etc.). The only FRAM I'd use would be the racing oil filter, but you'd need a remote filter housing designed for it.

What viscosity oil are you using? If you have good oil pressure, you probably could try the 0W or 5W Mobil 1 oil to reduce the pressure.

Just some of my thoughts. I'm sure others will have some good ideas (and stories!) on this as well.

MC
#14 GP VW Scirocco
 
Sure--I blew an oil filter right off a block once (wrong pressure relief spring) on start-up.

Sound advice to follow is from the above post; watch start-up reving and viscocity.

How much damage did you do when the motor puked its oil?
 
I've seen oil filters blow when the pressure relief sticks closed. I use a Canton filter (spin-on) w/ the replaceable cartridge. Minimal pressure drop, and works well. Plus, I don't need a filter cutter.

------------------
MARRS #25 ITB Rabbit GTI
SCCA 279608
 
In the HP Wabbit, I see about 80 to 90 psi at a cold start, and this is on an old, well used ITC engine that is being used as a mule engine for suspension development.

At 7000 RPM's, I see about 70 psi which works out to about 10 psi per 1000 RPM's. After the race, the oil pressure drops to about 25 to 30 psi in impound.

On a cold start, definitely let the engine temps (oil & water) come up before any rev's. Regards, Ryan.
 
Took the car out of the trailer last night. The Fram oil filter blew the seal. Pulled some caps off the crank and rods, bearings are toast, but crank looks good.
Both cases were with the engine at about 3000 rpm and fairly cold. I didn't do anything that I havn't done with my ITC 1.6 litre for years, but I guess the 1.8 can't take that.

Lessons learned:
1. NO Fram filters.
2. Don't rev a cold motor.
3. NO Fram filters.
4. Get a really BIG Idiot light.
5. NO Fram filters.
6. Pay attention to the idiot light.
7. NO FRAM FILTERS. (the official filter of SCCA)

Thanks guy's.
Mark
 
Mark,

The Fram race filters are ok, but as Mark (I think) said, you need a remote mount. These are the big suckers that hold ~ 1Qt.

Big idiot light is a good thing!

------------------
MARRS #25 ITB Rabbit GTI
SCCA 279608
 
Originally posted by Mark LaBarre:
Took the car out of the trailer last night. The Fram oil filter blew the seal. Pulled some caps off the crank and rods, bearings are toast, but crank looks good.
Both cases were with the engine at about 3000 rpm and fairly cold. I didn't do anything that I havn't done with my ITC 1.6 litre for years, but I guess the 1.8 can't take that.

Lessons learned:
1. NO Fram filters.
2. Don't rev a cold motor.
3. NO Fram filters.
4. Get a really BIG Idiot light.
5. NO Fram filters.
6. Pay attention to the idiot light.
7. NO FRAM FILTERS. (the official filter of SCCA)

Thanks guy's.
Mark
Click to expand...

A guy I met once got a new motor when his FRAM filter failed internally. The filter material came apart inside and blocked the outlet. He sent an estimate for a rebuild and the old filter to them and they sent him a check. Might be worth a shot.



------------------
Ralf
#53 ITB Golf GT
MiDiv
 
Gosh, I have been racing 4 years using regular Fram filters on my ITB 1.8 with no issues at all. This is the first time I have ever heard of anyone having a problem..
 
The 1.8L replacement pumps have a 60 psi relief spring versus the original 90 psi. I believe that this is an approved superceeding part # from VWOA for all 1.8L (at least that's what the dealer told me when they couldn't get the older pump). Unfortunately, most replacement pumps have 30mm gears (probably designed for hydraulic lifters) instead of the older 25mm, thus pumping more oil through that relief spring. The pickup assembly (with relief spring) is interchangeable between the pumps, but don't know legality for ITC. I too have lost an engine due to a failed filter o-ring. Don't remember brand but it was NOT german. Now, I ONLY use german Mann or OEM VW filters. Since then, I lost another engine due to a cracked mounting flange after a hit -- where a cheaper filter might have crushed more before cracking the flange -- oh well, sometimes you just can't win. On the same subject, I've also lost a clutch from blowing out a head-mounted pressure light sensor with the bellhousing plug out. Lower max pressure might have prevented that too.
 
You must log in or register to reply here.
Back
Top