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Originally Posted by Rookie
(Post 3084292)
Rage, I know pretty much nothing about a 496HO so excuse my ignorance. Has this engine been apart and modified at all? Does the 496 block have the same oil by-pass spring on the block that other Gen blocks have? I had a friend that his spring was bad or wrong so it by-passed a good portion of the oil and never cooled it. Also what is your timing, if I remember from another post years ago someone was having High oil temperatures and his timing was (I think) retarded to much and was creating High oil temps, (experts correct me if I'm wrong) also a lean condition can drive up oil temps.
Just throwing some other suggestions out there. Good luck My 496HO is heavily modified though still naturaly aspirated. An important fact seems to be that it is closed cooling as apposed to open cooling (straight sea water) so things are not as cool. I have replaced the 160F coolant thermostat with a 120F thermostat and the coolant peaks at 140F during long extended WOT running. Anecdotal evidence is that oil temperatures with open cooling run a lot cooler than when engine cooling is closed ie through a heat exchanger. Oil bypass in the block has been changed to 30 psi. Ignition timing is 28 degrees, same as GM's HP3 Vortec racing engine that I have emulated. I run 12.5 AFR at WOT which I am told is generally accepted as optimum range for a marine engine. Thanks again for your input. |
Originally Posted by Rookie
(Post 3084292)
Rage, I know pretty much nothing about a 496HO so excuse my ignorance. Has this engine been apart and modified at all? Does the 496 block have the same oil by-pass spring on the block that other Gen blocks have? I had a friend that his spring was bad or wrong so it by-passed a good portion of the oil and never cooled it. Also what is your timing, if I remember from another post years ago someone was having High oil temperatures and his timing was (I think) retarded to much and was creating High oil temps, (experts correct me if I'm wrong) also a lean condition can drive up oil temps.
Just throwing some other suggestions out there. Good luck Rage, if I read your posts correctly, 15 minutes seems like eternity to hold any engine at wot. Just my opinion. I have never come close to that nor would I. Does it take 15 minutes or almost 15 minutes before you are unhappy with your oil temps? If so, and if you could run that long at wot, I'd consider it a "back off" warning and give it a rest. Don't forget that pretty much everyone's product ratings are a "best case" scenario and anything maxed out for very long will come up short. From talking to you in the past I'm sure you know this. But with all due respect, how long would you typically like to hold it open before bumping the throttle down?? |
Originally Posted by Rage
(Post 3084428)
Thanks to all who take the time to share their thoughts.
My 496HO is heavily modified though still naturaly aspirated. An important fact seems to be that it is closed cooling as apposed to open cooling (straight sea water) so things are not as cool. I have replaced the 160F coolant thermostat with a 120F thermostat and the coolant peaks at 140F during long extended WOT running. Anecdotal evidence is that oil temperatures with open cooling run a lot cooler than when engine cooling is closed ie through a heat exchanger. Oil bypass in the block has been changed to 30 psi. Ignition timing is 28 degrees, same as GM's HP3 Vortec racing engine that I have emulated. I run 12.5 AFR at WOT which I am told is generally accepted as optimum range for a marine engine. Thanks again for your input. |
Originally Posted by SDFever
(Post 3084430)
Unless you're privileged, there is no adjusting timing advance on this engine. The timing on the 555 is non-adjustable without reprogramming.
Rage, if I read your posts correctly, 15 minutes seems like eternity to hold any engine at wot. Just my opinion. I have never come close to that nor would I. Does it take 15 minutes or almost 15 minutes before you are unhappy with your oil temps? If so, and if you could run that long at wot, I'd consider it a "back off" warning and give it a rest. Don't forget that pretty much everyone's product ratings are a "best case" scenario and anything maxed out for very long will come up short. From talking to you in the past I'm sure you know this. But with all due respect, how long would you typically like to hold it open before bumping the throttle down?? It all depends who I am running against as to how long I hold the pedal to the metal. Poker runs are only one example of notoriously extended hard running. It mostly depends on your disposition/goals. I do not want to be a slave to runaway oil temperatures. Thanks for your comments. |
Originally Posted by Rage
(Post 3084440)
My PCM555 ECU timing can and has been modified at my direction c/o Dustin Whipple as well as extensive fuel table modifications to get my engine modifications in line with appropriate AFR's / rpm.
It all depends who I am running against as to how long I hold the pedal to the metal. Poker runs are only one example of notoriously extended hard running. It mostly depends on your disposition/goals. I do not want to be a slave to runaway oil temperatures. Thanks for your comments. I have a budget and you do not. Man, I hate budgets. |
how about ,,to much oil volume,,going thru the cooler,to cool the oil down,,,,my thoughts are would a stock oil pump work better:eek:
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Too much oil
Originally Posted by TWIN-SPINS
(Post 3084468)
how about ,,to much oil volume,,going thru the cooler,to cool the oil down,,,,my thoughts are would a stock oil pump work better:eek:
I sent Rage a PM with more information which I will post probably tomorrow. I have someone checking my logic before posting. My opinion/What I'm thinking: corrosion or poor operation of the thermostat so it is getting excessive bypass, crud blocking flow in the cooler oil side, or aluminum oxide on the cooler inside. That oxide can be removed with toilet bowl cleaner left in the cooler for a couple of hours (clean first of course). The cooler design is fine. It's something else. Rage: What's your next step? Do what I said in PM for the stat first and clean it off. Or, if you pay the shipping, I'll send you a new one just to see if it fixes it. Note we're a competitor, so this isn't warranty. Russ |
icky icky air
Quote from you: "...My 496HO is heavily modified though still naturaly aspirated. An important fact seems to be that it is closed cooling as apposed to open cooling (straight sea water) so things are not as cool. ..."
Rage: This is important. If you're getting air in your incoming water (of course you are), every air molecule in essence does NOT transfer heat (well not much). This can substantially reduce the efficiency of the cooler. You might just need a bigger one to compensate for the lack of efficiency. You're sealing off the cooler early on so it's not engine temperature. As fast as you're running, I don't know how you'll keep the air out. Maybe you'll need to up size? Did it ever work at any point in time? If not, I'm more leaning this way now. I think the logical reason you're increasing in temp over time is that the cooling system (flow, hardware, etc) can't compensate for the engine's heat rejection. Consider the other things I wrote (not the cleaning yet) and post the results. Russ |
Rage are you running a stock oil pan? If so what oil level are you running? Innovation found windage issues back in 2002 and made some mods.
Thanks Steve |
would sea strainers help,,,if not the reg size,,, the larger ones , iam wondering if the larger volum would help reduce the air in the water problem you mr.cooler,,,talks about,,
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