| Author | Message | ||
     Gabriel Guay (Gearhead) Member Username: Gearhead Post Number: 77 Registered: 04-2002 |
Bill, Question for you. My gauge is machanical as well as yours. I chose to add an Oil gauge because when ever its between 30 & 40 degrees F. The first start in the morning will produce some light lifter tapping and what sounds like a light rod knock for about 1-2 seconds. I always felt this was due to oil drain back and that it takes too long to prime up the pump. By the way, this never happens if its colder or warmer. Now I have the oil gauge instead of a stupid light, I can see whats going on and I suspect a bad Oil press relief valve or bad oil pump seal. When I started up this morning. Oil light goes out almost instantly as normal, light lifter clatter and light rod rumble for 1 second but, Oil press is only at 10-15 PSI and rising very slowly. Changing engine speed from 750 RPM to 1500 and back makes no diff on oil presure. Still steady slow rising to 25 and finally 30 PSI after about 30-40 seconds. Seems too long to me. The weird thing is, It stays dead on 30 PSI no mater if at idle or 2500 RPM. So I start to drive to work. As soon as water temp reaches norm temp, Oil Press rises to 38 PSI and stays dead on 38 with a few momentary bumps to 40 PSI. Again even at idle, it only drops from 38 to 30 at 650 RPM. Seems like it's regulated at 35 PSI. I will take out the oil press relief valve Saturday and see if the spring is 60 mm as stated in workshop manual and inspect valve piston for evedence of getting jamed in open position but, would like to hear what normal oil press looks like on your truck. By the way, running 5W50 synth GG | ||
| Bill Bettridge (Billb) Dweb Lounge Member Username: Billb Post Number: 1399 Registered: 02-2002 |
Wow - that's along time to come up to pressure with 5w50! Also your oil pressure when warm is low too. Mine with 10W30 will come instantly up to 52 psi upon cold startup and quickly settle to around 48 or so. After fully warm it will stay at 46-48 psi at any engine speed above 1500RPM and at idle it will drop to 25-30 or so. Bill | ||
| Gabriel Guay (Gearhead) Member Username: Gearhead Post Number: 78 Registered: 04-2002 |
Follow-up on Oil pressure relief valve. Well, I had an engine oil cooler hose that was leaking at the crimp and the new hose came in from AB today, so I swaped out the hose today. Made a mess of my drive way but, I expected that. Once that was done, I took off the retaining clip on the relief valve and the cup and spring came right out but, the piston stayed in there. I measured the spring and it's free length is about 54 mm. Work shop manual says it's sopposed to be 60 mm. Sprayed a little WD40 in the bore and the piston slid out. Didn't see any scratches or evendence of the piston getting stuck. I think the spring is weak. I shimmed it with a washer making the total combined lenght 58 mm just to see if I was right about the spring being bad. Put it all back togather and now comes up to 40 PSI in about 1 second and stayes at 40 PSI. Warm or cold. Idles at 30 PSI warm and anything over 800 RPM back to 40 PSI. I am tempted to shim it up one more washer but, I'll leave whell enough alone until I get a new spring. Don't know if AB or Rovers North has them but, worst case I think I can get one at the dealer. I really feel like my oil pressure was just bleeding off at the relief valve. Then again, it does have 120K miles but, runs strong and no clatter or rattle now that the spring is shimmed. Might just get out of this without having to by a new oil pump & cover yet. Trying to make it last another season. Planning overhaul in next 10 months or so but don't want to grenade it before then. Thanks Bill. I'll use your oil press as a bench mark to judge oil press when I fit a new spring. Hoping for the best, GG |
