Idasho Posted December 30, 2012 Share Posted December 30, 2012 What kind of temps are you guys seeing? My high compression EA81 mated to a 5-speed D/R is still in its break-in stages, but Im slightly concerned about oil temps at higher RPMS. I currently have about 1500 miles on this new motor. Here is a run-down to cover the bases... Zero mile rebuild all new bearings all new seals heads decked .0015 fresh valve job + new valve stem seals new ea82 pistons New ea82 rings new oil pump new water pump new distributor new rotor/wires/plugs new radiator all new coolant hoses new OEM t-stat running WITHOUT EGR Weber carb (okay tune, havnt touched it since swapping from old motor) Currently running 10degrees advanced Currently the motor is running fantastic, and coolant temps are always in the green. What I am concerned about is the oil temps. During the early stages of break-in I was seeing some high oil temps, which is expected with a new motor. Around town the oil temps would creep up to 200 or so and stay there. On the highway with sustained runs at 3000rpm the temps creep up to 250 or so and stay. Regardless of up/downhill. 3k RPM with the 5-speed puts me between 60 and 65mph with stock tires. But If I push it past that 3k rpm, like dropping into 4th gear and reving to 3800rpm the oil temps immediately start creeping to the red zone. Ive seen as high as 280 so far. The same happens on sustained high rpm drives on the flats. Just yesterday we drove back from Pasco, running 70mph on freeway and the same happened. I had to back it off to 65 to get the temps back in the green. It is running good though, we averaged 28MPG on the 300+ mile trip. Not bad for a lifted rig with a roof rack I think. I know that a new motor will always run the oil a bit hot, as clearances are much tighter. But this has me concerned. Oil pressure is always good. Even when the oil temps get that hot on the highway Im still seeing 50PSI, and always at least 15PSI/1000rpm throughout the rev range. Currently running a 10w40 dino oil. Once broken in completely it will be changed to a 10w30 synthetic. Long post, thanks for all who read, and any insight is very appreciated Link to comment Share on other sites More sharing options...
skishop69 Posted December 31, 2012 Share Posted December 31, 2012 I haven't done my hipo EA81 build yet, but having built several 350+HP engines I can tell you hitting 300 degrees is not uncommon. You can buy the Nissan spin on oil cooler adapter, run a cooler and keep it down around 250 if you're that concerned. Cooler is better with the oil. Link to comment Share on other sites More sharing options...
Idasho Posted January 1, 2013 Author Share Posted January 1, 2013 I know the temps are not anything to worry about as far as max oil temps go, but Im curious as to what other EA81s are seeing. This is the first time Ive had an oil temp guage on one. And if the temps do not stabilize more as the motor breaks in and clearances loosen up, I think I will opt to go for a remote filter along with a t-stat controlled cooler. Link to comment Share on other sites More sharing options...
Idasho Posted January 1, 2013 Author Share Posted January 1, 2013 Well, I think I found the problem. With this motor still being very new, I have been giving it a check-up every few hundred miles. I did just that today. I found a bad dizzy advance. Luckily I have a couple of good used dizzys on the shelf. But this one (napa reman) has less than 2000 miles on it. And it WILL be going back Ad far as I can tell, the dizzy was jammed fully advanced. I thought it felt funny recently. I had some strange off throttle and steady throttle surging. I attributed it to the Weber needing a tweak. here is what I found: Since dropping in a good dizzy and retiming it, highest oil temps I can get the gauge to read is 240 Link to comment Share on other sites More sharing options...
naru Posted January 1, 2013 Share Posted January 1, 2013 Breaker plate on that one is badly worn. Magnet should not flop around like that. Is that the "rebuilt" one? Link to comment Share on other sites More sharing options...
Idasho Posted January 2, 2013 Author Share Posted January 2, 2013 Yeah, thats a napa reman. Less than 2k miles on it. Definitely wasnt that bad when installed. I think part of the plate actually broke. Link to comment Share on other sites More sharing options...
carfreak85 Posted January 4, 2013 Share Posted January 4, 2013 On my EA81T with the factory, thermo-controlled oil cooler, the Autometer oil temp gauge I have installed in the oil pan is usually pretty high. I think oil starts to break down around 260*F and my car is usually over that... Maybe the thermostat in the filter sandwich is stuck closed on my car? Anyway, 240*F in the winter is still darn hot. Keep an eye on it as the ambient temps start to creep up. Make that trip to Pasco in the summer and I'd be willing to bet you'll be over 260*F. Link to comment Share on other sites More sharing options...
skishop69 Posted January 4, 2013 Share Posted January 4, 2013 Thermal breakdown is dependant on many factors. 260 is the general rule of thumb. With todays oils and additives, that number applies mainly to 'cheap' oils. High quality synthetics will withstand 350 degrees. The downfall of multi viscosity oils are the VI's (viscosity improvers). These additives actually have a negative effect on the resistance to shearing force which is one of the main causes of breakdown. Synthetics don't suffer this problem as their engineering includes high resistance to shearing. Straight weight oils are best at resistance to thermal breakdown and shearing. That's why they are recommended for high rev/load, air cooled engines. Your best choice would be a synthetic, straight 30 given that you are not in a cold climate, then I would say 20. In the case of your timing being full advanced, your combustion temps were excessively elevated causing the oil temp you saw. The adapter and a decent 6 pass sandwich cooler will put you around 220 now that you've fixed the timing issue. Link to comment Share on other sites More sharing options...
Idasho Posted January 5, 2013 Author Share Posted January 5, 2013 Maybe the thermostat in the filter sandwich is stuck closed on my car? Anyway, 240*F in the winter is still darn hot. Keep an eye on it as the ambient temps start to creep up. Make that trip to Pasco in the summer and I'd be willing to bet you'll be over 260*F. Fortunately oil temp is not directly related to ambient temp. When you DO NOT have a cooler anyways.... But I will be watching it, and am currently eyeing a few different style setups. It would be nice to not have to drop the skid plate to do an oil change, so a removed filter wold be cool. I just need to decide on which particular t-stat relocation plate to get. So it will be a remote filter, with a t-stat cooler. Unfortunately many of the t-stats I see start opening at 180 degrees or so. Id rather have one that opens closer to 200. Link to comment Share on other sites More sharing options...
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