Oil pump shim

[Rawze]

(04-10-2016 )Mrkentee Wrote:  Mine was done 19,000 miles ago. Over 60 psi at start. Stays between 40 & 50 depending on rpm & temp.

60 PSI is rumored to be enough to cause Baldwin filters for Cummins ISX engines to sometimes fail internally.

[Mrkentee]

(04-10-2016 )Rawze Wrote:  

(04-10-2016 )Mrkentee Wrote:  Mine was done 19,000 miles ago. Over 60 psi at start. Stays between 40 & 50 depending on rpm & temp.

60 PSI is rumored to be enough to cause Baldwin filters for Cummins ISX engines to sometimes fail internally.

I use Fleetguard.

[slowpoke]

just shimmed my oil pump again had 5 dimes, now upped to 8 soon as i start engine oil pressure only climbed to 32 psi (used to be 42 when cold) then fluctuated to 28 back to 32 up and down for about 4 minutes then climbed to 45 at 900 rpm once it settled i raised rpm to 1300 and it hit 51 psi. what pressure does the bypass ontop of oil filter blow of at. i pulled allen plug out to check thats its up datted it is. didnt try to pull it out though. could that be what caused fluctuation was a little scarry. bolts in oil pump o ring to out side by cotter pin. oil filter 2 days old.

[jimeneztrans84]

I have about 75k miles with my shimmed pump and no issues so far. I shimmed with 7 or 8 dimes if I can remember. You will get more oil seeping if you have external leaks which I do....

[slowpoke]

just fired it up after it letting it cool and same thing started, if i let it idle at 600 rpm pressure actually comes up to 38psi, increase idle to 850 pressure starts to drop down weird. Well i guess i'll wait till i go down the road and see what happens when it gets heated up, just don't know what else can dump oil pressure then return to normal. If pressure is good going down the road then i'm going to try a thinner synthetic, maybe.

[jorden486]

Put a manual gauge on it. Don't trust the sensor.

[Rawze]

(05-20-2017 )slowpoke Wrote:  just fired it up after it letting it cool and same thing started, if i let it idle at 600 rpm pressure actually comes up to 38psi, increase idle to 850 pressure starts to drop down weird. Well i guess i'll wait till i go down the road and see what happens when it gets heated up, just don't know what else can dump oil pressure then return to normal. If pressure is good going down the road then i'm going to try a thinner synthetic, maybe.

If mine went haywire like that after doing a mod to it, I would find out why. Perhaps your shims are in the wrong place,.. or have gotten lodged where they should not be. Not worth the entire engine failing to go monkeying around like that without knowing 120% what you are doing. Besides that, anything much above 45 PSI peak or so, and you are looking at the fly-wheel housing having high risk of leakage on an older engine. To fix it, you are looking at removing the tyranny and doing a lot of work to replace that FWH gasket if it fails because you are pushing oil pressure up so high.

[slowpoke]

pulled the spring out of dog bone and placed 8 dimes in cup of dog bone inserted spring into dog bone pushed all in.is that okay to do? wasn't easy to force cup in, I didn't buy new o ring though, wonder if i scrapped o ring a bit. i did pull all apart checked all eight dime's there . cant buy new o ring holiday up here in canada till tue. going to put manual gauge on as suggested by jordan486 see what happens. so theres nothing else that can relive pressure ?

[Hammerhead]

(05-21-2017 )slowpoke Wrote:  pulled the spring out of dog bone and placed 8 dimes in cup of dog bone inserted spring into dog bone pushed all in.is that okay to do? wasn't easy to force cup in, I didn't buy new o ring though, wonder if i scrapped o ring a bit. i did pull all apart checked all eight dime's there . cant buy new o ring holiday up here in canada till tue. going to put manual gauge on as suggested by jordan486 see what happens. so theres nothing else that can relive pressure ?

Placing the dimes in the dogbone cup is how I do and recommend it. Placing them in the end of the pump has some (small) risk of them not ending up seated properly, unless it's done with the pump fully removed and the bore being vertical as in Rawze's overhaul video series.

An O-ring should be fairly easy to source, Home Depot, Rona, Canadian Tire et al should carry these and they are open this Victoria Day weekend.

I recommend to chamfer the bore opening, as I found mine to be quite sharp, and reinstalling the assembly requires significant effort once shimmed, making centering the end piece with the o-ring less than a simple task. If you decide to chamfer, place a rag or paper towel in the bore BEFORE chamfering to avoid possibly contaminating the pump with metal debris. Of course common sense also says to make sure the oil pan is NOT under the pump while chamfering.

The two possible pressure relief points are;
1)The 150psi relief valve in the oil pump itself. When this relief opens, it dumps the excess pressure directly back into the pan. Unlikely.
2)The oil filter bypass located on the oil cooler directly above the oil filter header. This is the larger of the two Allen head plugs clearly visible. It's purpose is to allow engine lubrication when the oil is too cold to flow through the filter media sufficiently, or if the filter becomes compromised. If you have not updated this relief valve, it is possible that this bypass is allowing some of the oil flow to bypass the filter. Possible.

3)The most likely is that your oil pressure sending unit is getting weak. A manual gauge will verify. If anybody ever asks me about oil pressure, this is the very first thing I tell them to change. It is the most likely component to fail, and even if it hasn't failed, now you have a spare. And every owner/operator should have a spare oil pressure sending unit. Total sensor failure results in engine shut down. Being towed for a $50 sensor that is easily replaced, from my standpoint is unacceptable.