oil pressure problems from stock hardware
 

I'm posting this thread to help out some of you guys who are having serious oil pressure problems. I see guys on this bd alot asking questions about oil pressure issues,oil temp issues etc,i'm going to show some potential problems that might be causing alot of your grief.I am not a expert by any means BUT I have had the same problems and questions when i started modifying my original gen 6 502 5 years ago. Your oil systems need to be "optimized" to make your motors live,it will cost you a few dollars BUT do you really want to be rebuilding your motor twice or missing valuable boating time? A stock 502 or 454 has a tiny oil cooler and tiny fittings thru out the stock oil system.When your motor is still original everything works ok because a stock motor has very tight rod and main clearences (under .002) and has a std volume oil pump. The average guy builds up his motor,rebuilds a blown up motor or finds another motor and builds it up,typically you end up with rod and main clearences around .0025-.003. Sure,if you can find a super high quality machine shop that can hold tolerances perfect you could run things tighter but typically those clearences are what you end up with. The first thing you have to do is run a high volume oil pump( yes,everyone knows this) but heres where the problems start-if your running a gen 5 or 6 block and it started life as a crate engine,it has 11lb bypass relief valves. If your motor has unknown origin,who knows what it could have. Buy a new 30lb bypass relief valve for the outside(the one near edge of block casting for filter adapter) or plug it off,they are available at your local chevy dealer part #25013759,they are under 5$. The middle valve directs oil to the cooler fittings on side of the block that are not used in boats,leave it out completely. These valves open from a pressure differential,if your high volume pump puts out enough gallons per minute of oil to pump lets say 8 gpm and create 75 psi and your stock system will only flow 6gpm at 55psi then your block bypass will open and your oil will not go to your cooler and filter. Your motor will then get unfiltered hot oil. The new 30 psi valve will help to prevent this from happening.

Re: oil pressure problems from stock hardware
 

The next thing you need to do if running a high volume oil pump,looser clearences and more horsepower than stock-TAKE A GOOD LOOK AT EVERY FITTING,ADAPTER AND LINE in your oil system. Most likely you need to completely replace all of it. The stock merc stuff for a gen 6( and probably gen 5) is JUST TOO SMALL.Here is a example-the stock gen 6 block adapter has a .390 dia discharge hole-THAT IS BARELY 3/8's of a inch. Just to show you what i mean i stuck a 3/8"s bolt thru the hole in 2nd pic. Even with a 30 lb block bypass valve it is so restrictive that you could still make the bypass open or worse,make the regulator on the pump open in the pan reducing your output and causing low oil pressure.

Re: oil pressure problems from stock hardware
 

There are several afternarket companys selling block adapters and remote oil filter mounts. This is a pic of a old one i had on my gen 6 that cp performance sells compared to a stock one. The discharge hole is almost 5/8"s instead of 3/8"s.

Re: oil pressure problems from stock hardware
 

The stock filter adapter is no better,here is a pic of a aftermarket one,i couldn't find the stock one to compare it but it has the same tiny hole that the block adapter has.This one uses -12 an fittings with big high flow passages.

Re: oil pressure problems from stock hardware
 

OIL COOLER-your stock oil cooler on most gen 5/6 blocks looks like this,smaller dia then a beer can with tiny .390 dia pasages where fittings screw on .You can see from 3/8"s bolt in the hole how restrictive it is.When your motor made 415hp it was barely big enough,now your asking this tiny cooler to cool your oil,its not going to do much. Buy a aftermarket cooler,they are much bigger than stock,will actually cool your oil and will allow you to get rid of all the factory oil lines and fittings.

Re: oil pressure problems from stock hardware
 

Oil lines-the factory oil lines have tight radiuses on them and inverted flare fittings that only fit your factory adapters and cooler. They are as small as 3/8 inch id also and canot flow as much oil as a high volume pump can put out. Preferably you should run all your oil lines in -12 an(rusell,aeroquip etc),it is generally 5/8"s id and if you have to use alot of 90 degree fittings or adapters your smallest adapter will be at least 1/2 inch id. You want to run your oil lines as short as possible with as few bends,turns and adapters.If your factory oil cooler is on the opposite side of motor from where your block adapter comes off,move it. My gen 6 had about 12 ft of hose from factory to reach the tiny stock oil cooler. Every 90 degree fitting and tight bend increases the amount of restriction to oil flow. Avoid hydraulic hose with high pressure ends from industrial suppliers,if you look carefully at the fittings the adapters and ends often neck down to less than 1/2 inch,even on 5/8" or # 12 hose because it is so heavy duty to give it the 4000 or 10,000 psi rating.The proper way to route your oil lines is go from discharge on block(outside fitting) to filter inlet on (which is ouside ports on filter)filter adapter to oil cooler back to center fitting on block adapter. If you spin a rod bearing or chew up parts in your motor replace your oil cooler or have it professionally flushed,squirting carb cleaner or dumping paint thinner thru it and blowing it out is not good enough.Don't trust some flunky at the local marina to do this for you if they are installing your motor. There are tiny pasages that can trap metal and it will get loose later and wreck your new motor.

Re: oil pressure problems from stock hardware
 

Last,run a high quality,high flow oil filter. I run a K&N high flow filter or a fram hp series race filter. The flow ratings of these filter exceeds what the oil system can flow so it should never be a restriction. I mounted mine so i can put a coffee can under neath it when changing oil so oil doesn't run everywhere.You can see it to the right in the picture. I hope this info helps some of you guys out there that are struggling with oil pressure issues. If i left anything out feel free to add it,Smitty

Re: oil pressure problems from stock hardware
 

Great job Smitty!

Re: oil pressure problems from stock hardware
 

Nice informative thread!


Gerry

Re: oil pressure problems from stock hardware
 

Way to go Smitty!

I been running 250 to 280 oil temp on my 502mpi Whipple motor when running long distances. I think I need to go the route you have taken on this issue.

Thanks again! :D

Re: oil pressure problems from stock hardware
 

Good info Smitty. I would add a suggestion that engines above 500hp use a 3 x 18 oil cooler. However, these coolers have enough cooling capacity that your oil won't warm up if you're just cruising around. So you also need an oil thermostat and oil temp guage also. Especially up here in the north country. I have had 2 friends spin bearings early in the season from running hard with cold oil. It can also cause nasty condensation problems.

Re: oil pressure problems from stock hardware
 

Good info here Smitty,
On my gen 4 motor I plugged the bypass in the remote filter adapter and drilled out the oil passages both there and in the remote filter pad for better flow.

Braided line or pushfit line fittings are available with radiused 90* fittings that flow much better than the hard 90* fittings and are intended for oil lines. Cost a lot more though.

As far as braided line goes, it looks good but after a few years it starts to fray and is painfull to work around. I plan on replacing most of mine with pushfit lines and fittings over the next year.

My experience with oil coolers and after market 600hp is that a large cooler such as Teagues 4" offshore cooler is needed in the south with our high summer water temps. That was my 3rd cooler BTW.

I measure oil temp in the pan before the cooler. I know some measure after the cooler but I dont see the point in that.

Re: oil pressure problems from stock hardware
 

That brings up another question. I have 502mpi with a whipplecharger. Live in Texas on the gul coast. We average 90 plus on daily basis. I know the water temp is also warm. What is safe oil temp for an engine in this enviroment?

Thanks :D

Re: oil pressure problems from stock hardware
 

I think most would agree that 280* is too much for a non-synthetic oil. I assume that you are measuring oil pan temps.

250*/260* is where I get to after a hard run with 160* water temp. I am running Mobil-1 v-twin 20/50 at 50 hour changes (see Hydrocruisers oil thread). Mobil-1 15w50 is a good choice also. 280* wont hurt a good quality synthetic with say 25 hour changes. But 230*-240* would be more of an ideal temp.

if you are measuring oil temp after the cooler, then your actual temp is 25* to 50* higher and you are pushing your luck IMO.

Re: oil pressure problems from stock hardware
 

The oil cooler I'm running came from cpperformance and it has a thermostatic bypass tube built on the side of it. I don't have a oil temp gauge but ive always had good pressure since upgrading the original gen 6 and also with my current mk4 but i still haven't ran it this year (still waiting on tailpipes),might be a different story with the extra 200 plus hp i have over last year,Smitty

Re: oil pressure problems from stock hardware
 

Hey Smitty:

Excellent job and great pictures that will save a lot of people some real headaches and dollars with their oil systems. this is exactly the kind of information and assistance that considerate sharing members like you can do for the other forum readers. I salute your contribution. Well done, Kudos!!

Ray @ Raylar

Re: oil pressure problems from stock hardware
 

Now if we could get Admin to keep this thread near the top.....

Re: oil pressure problems from stock hardware
 

I have had several phone conversations with a couple of members who have oil press problems and the hardest point to get thru is the stock stuff is just pure and simply too small and restrictive. Adding a big oil cooler is great but if oil can't make it out of block it won't help!Smitty

Re: oil pressure problems from stock hardware
 

Ive seen a zillion part #'s flying around for oil filters on this board,I stick with K&N 6002(its extra,extra long),has550psi burst strength,filters down to 10 microns,has anti-drainback valve,built in bypass valve (which with all the surface area should never open),flows 12-14gpm and if you were real anal you could safety wire it,it has provisions.If you don't have room the 3002 fits where any ac-35 style filter will,Smitty

Re: oil pressure problems from stock hardware
 

One more pic-stock,K&N-3002,K&N6002

Re: oil pressure problems from stock hardware
 

Good info Smitty; especially about bends, elbows and fittings. When I was redoing a pair of 502s I took the opportunity to change the oil plumbing. whoever did it before had used 3 brass 90s between the block adaptor and the oil filter housing. I also changed the bypass as you said, eliminating the 4@90 degree turns within the block (that passage that directs oil to GMs oil cooler connection.) Getting rid of those restrictions means more pressure and flow actually gets to the engine.

How is the boat running?

Re: oil pressure problems from stock hardware
 

I just got the new tailpipes 2nd day air today so boat will hopefully be running in the water before weekends over. I would have been done today except i got roped into fixing a stranded travelars transmission at last minute today . The simple 3 hour job turned into 8 hours of hell!:( . You know how it is having a business,your family and BOAT come last,Smitty

Re: oil pressure problems from stock hardware
 

I also had oil temp and pressure problems on my modified 502 MPI's. Had temps that were going to 300 degrees on full throttle runs. I purchased the entire setup from the 2002 500EFI including the oil cooler that mounts in the back and the steering cooler. their housing that mounts to the block has a thermostat and a pipe opening where I mounted a oil temp sending unit. I also took out the elec oil temp guages and ran mech oil pressure guages. All oil and temp problems are now gone and engines stay in normal ranges. The only drawback is the cost, but everything bolts in perfectly.

Re: oil pressure problems from stock hardware
 

^^

Re: oil pressure problems from stock hardware
 

From the posts I have read from Wobble...he is now my CEO...Wobble knows his stuff!!

Welcome to Hydro-Oil :D

How long have you beeen using Mobil-1 filters and Mobil-1 20W-50 V-twin? ;)

Re: oil pressure problems from stock hardware
 

the owner of the shop that dynoed my motors told me synthetic oil is a waste of money...i think i'll be running the m1 v-twin as good oil is less exspensive then engine parts

Re: oil pressure problems from stock hardware
 

I had same experience on baker engineerings chassis dyno. We tuned car until we had the highest hp/tq numbers at full operating temp then changed oil to a high quailty synthetic oil(sentinel) and saw 15-17 ft lbs of tq average at peak on 3 runs in a row over valvoline racing oil. This was on a car that only put 250hp to the tires,we thought the dyno operator would be interested (after he insisted it would make NO noticable difference) but he said because he never heard of it he would never run it? :rolleyes: ,Smitty
Hydro,i recently talked to carlos at sentinel and he wouldn't give me exact percentages but he said they have a high zddp level,their base stock is a partial diester blend and of course they have a high level of virgin molybendmium dissulfide indefinately suspended in their oil,Smitty

Re: oil pressure problems from stock hardware
 

Thanks for the great advice,and your time smitty.

Re: oil pressure problems from stock hardware
 

Vandeano,this is the oil thread that should enlighten you,Smitty

Re: oil pressure problems from stock hardware
 

I just had to bring this one back up. While I was working on my engines, I remembered that someone hed asked how to plug the oil bypass. I had this done at the shop that rebuilt my engines because this way all oil goes through the filter and cooler. I was told to watch my oil pressure gauges to make sure that the filter wasn't getting plugged. So far with normal oil changes, I haven't noticed any change in oil pressure. You can see from the picture it is a 20mm dia. freeze type plug driven in and staked in four places.

Re: oil pressure problems from stock hardware
 

Thanks Smitty for starting this thread ! I'd like to add that the main oil passages can be drilled in the block as well as the intersecting oil passages , to give the mains more oil.
Also 3/4 groove H series bearings work well to provide a more continuous film of oil to the crank journals. Also a cross drilled crank provides better supply of oil. BBB

Re: oil pressure problems from stock hardware
 

I did mine the same way.

Good thread Smitty.It will help a lot of people!!

Re: oil pressure problems from stock hardware
 

Bump :D

Re: oil pressure problems from stock hardware
 

I am having trouble getting my oil temps up. I have bell housing coolers that seem to work too well. I can idle all day and the temp will not go above 140 degrees. At cruise it gets to about 180 degrees. I run cross overs with no water t-stat. Oil pressure runs about 70 PSI at cruise. Water pressure runs from 5 PSI at idle to about 18 PSI at cruise.

I have looked at several oil thermostats (PermaCool, Earls, Hardin, Merc, etc.). They range from $40 to $250 and all seem to do the same function. Any specific recommendations for marine use? Why?

Thanks,
Doug

Re: oil pressure problems from stock hardware
 

I used Permacools last summer but they require a ton of hoses and fittings. This year I'm switching to Earls sandwich type http://store.summitracing.com/defaul...h.asp&x=26&y=9 They eliminate a couple of the hoses and makes for a neater installation.

Re: oil pressure problems from stock hardware
 

It seems like one solution would be to run a water t-stat in conjunction with a water pressure relief valve. This would stabilize your water temp and probably raise your oil temps.

I would recommend a sea strainer also if you go that route

Re: oil pressure problems from stock hardware
 

A lot of supercharger engines run wihout water thermostats to help control detonation. They work fine with the addition of an oil thermostat.

Re: oil pressure problems from stock hardware
 

ttt Time to bring this back up.

Re: oil pressure problems from stock hardware
 

Witch one of Earls sandwich style oil thermostat will fit mercruiser remote filter adapter. There are 2 different # numberer's only one fit Chevy, but not 454 Cui? :evilb:

Re: oil pressure problems from stock hardware
 

Anyone using the revolution marine oil cooler?