oil filter rubber ring blowing out on cold startup - Diesel Forum

darylz · 12-10-2005, 06:02 PM

I have a 92 F250 with the IDI 7.3 diesel. Recently a problem poped up where on cold startup the rubber ring on the oil filter blows out and the oil starts flowing out in buckets. I have tried 3 different filters, a motorcraft, a fram and a Navistar dealer filer. It used to do this once in a while, not I can not even start the motor without it happening. I replaced the CDR (crank depression regulator) thinking it may have been causing too high a pressure in the crankcase and therefore causing high oil pressure. Did not resolve it, first time I started the motor after replacing the CDR the gasket blew out again. There is definitely too high an oil pressure, but I can not figure out where it is comming from. While running the oil pressure gauge shows normal oil pressure, until most oil flows out, then goes low. This only happens on startup. In the past, once the motor was started cold, it could be restarted many times without any problems before it was left overnight. The oil cooler flange is nice and smooth and nothing is left to obstruct the filter ring from sealing between the filter and flange. It blows out once the motor fires. Does anyone have any ideas? Thanks.

Birken Vogt · 12-10-2005, 06:29 PM

Oil pressure regulator is sticking shut, and oil pressure gauge on this truck is a simple on/off switch that only shows good pressure above about 7 psi, and once it falls below that shows zero.

Birken

Mr_Roboto · 12-10-2005, 06:38 PM

Most oil pumps have a pressure relief valve inside of them to prevent excessive pressure. It's spring loaded, when the oil pressure exceeds the spring pressure, the valve comes off its seat and relieves oil until it is under the max pressure again. Works just like an air compressor pop-off valve.

If this valve is sticking or frozen, it would cause exactly what you describe. Also, if there is excessive oil pressure, you run the risk of oil pump drive failure due to overloading.

As far as the oil pressure guage reading normal, many Ford trucks did not have a true variable sending unit, only an on/off switch and a resistor intended to make the guage read somewhere in the normal range as long as there was *some* oil pressure. I can't tell you for certain if this applies to your truck or not.

*My suggestion*. Drain your oil, replace it with some nice, light oil (5w30 or thinner if you can find it). Get a good detergent additive (Rislone etc) and run that for a few days. If the relief valve is varnished up, hopefully the detergent will get it to loosen up.

(Yea, I know 5w30 isn't diesel oil. The biggest difference in diesel oil is it's soot suspension additives, which should not be an issue for short term use).

cdnsarguy · 12-10-2005, 06:41 PM

My first question would be how many turns after gasket contact with the header face do you do, 1.5 -2.0 is the right answer.

On all fleetguard filters it is pictured on the side for correct installation. I believe the VOmanual 7.3 diesel suppliment also explains the correct installation as 1-2 turns, you must use the same tool to install as remove, hand tight does not do it...........

Mr_Roboto · 12-10-2005, 08:27 PM

I've never tool tightened a filter on a 6.9 or 7.3IDI, and never had a leak much less the seal blow out. I simply hand tighten them, albeit gorilla hand tight.

darylz · 12-10-2005, 08:31 PM

I have gone at last 1 turn past contact in tightning the filter with all filters, as far as the filter would allow me to tighten it. How long do you think I should run the lightweight oil in the engine with the detergent to see if it would unstick the valve and what type of detergent should I put in it? thanks.

rcoakley · 12-10-2005, 08:40 PM

Not sure if I read the original post correctly. [img]/ubbthreads/images/graemlins/shrug.gif[/img]

Does the filter blow on every startup?

darylz · 12-10-2005, 09:02 PM

at this point yes, it blows everytime I try to start the engine. where exactly is the pressure relief valve? I was looking at oil pump prices and saw something that said the relief valve was on the oil filter flange of the oil cooler. Is that correct, or is it in the oil pump? thanks.

OkieGringo · 12-10-2005, 09:39 PM

The "oil pressure regulating valve" is on the rear cooler header, the plug closest to where the cooler tube joins the rear header casting on it's left/front face. It is not the one facing the front of the engine, but the one facing the left side of the truck. The "oil filter bypass valve" plug is on the rear header lip on the driver's side just above where the filter spins on. OkieGringo

darylz · 12-11-2005, 07:44 AM

which do you think is my problem then, the pressure relief valve or the pressure regulating valve? Are they the same? I would think one would be in the oil pump, but at this point I am confused. If it is in the oil pump, is it possible to raide the motor and remove the pan without having to disconnect everything? thanks again for all the input.

OkieGringo · 12-11-2005, 09:38 AM

[ QUOTE ]
which do you think is my problem then, the pressure relief valve or the pressure regulating valve? Are they the same? I would think one would be in the oil pump, but at this point I am confused. If it is in the oil pump, is it possible to raide the motor and remove the pan without having to disconnect everything? thanks again for all the input.

[/ QUOTE ]

They are not the same thing, BUT, they are both accessible from OUTSIDE the engine/pan. Remove the 'plugs', the valves are right there. Be careful, I can't remember which one is spring loaded and will shoot out and find "The Murphy Place/Hole". Clean them up or replace. Got a digital camera? Take photos of each step and we'll help ya thru it. OkieGringo

Mr_Roboto · 12-11-2005, 10:06 AM

Sounds like it's repair manual time... Unfortunately, I have not been INSIDE one of these diesels (and I hope not to be knock-on-wood) so I can't tell you for sure.

Like I said, I'd try cleaning the system first, the problem is probably varnish buildup.

John Wood · 12-11-2005, 10:43 AM

Hi Darylz,

I would try the engine flushes that you can buy. On occasion, when I do an oil change I dump two bottles of the engine flush in to the engine and follow the instructions on the label ( I use two bottles as the sump capacity of our engines is approx. twice that of a gas engine). I like to think this helps clean out the varnish and material that could otherwise buid up over time and it could very well work for your situation. Once I have dumped the treated oil and drained the engine for a while, I fill up with cheap oil (still with dirty filter) and run just for a minute or so, to flush out the system. Then, after letting it sit for a while to drain, empty the oil and put on a new filter. Then refill with the good quality oil.

I assume this is benificial to the engine as the engine internals are clean (i.e rocker gear and top of heads). I do this every second or third oil change.

Might be worth trying on your truck.

HTH

John

mgraveman · 12-11-2005, 03:31 PM

I don't know if I agree. At idle, these things are only at about 10-15 PSI. Nothing in the pump could cause it to be high. A blockage in the block could do it though. It is possible that these cleaners might work, but he has to start the engine to use them, and it'll run all out of oil if he does.

I would put a oil pressure tester on it before I do anything. If it's lower than 100 PSI, replace the oil cooler. You may just have a warped flange, not keeping that O ring tight. If it's higher than about 100, remove the engine.