525 EFI overheating the oil?
 

The center motor's oil is overheating? Noticed the belt was very loose, it would not even turn at idle. Changed out the belt and put in a new water impeller. The oil cooler is not blocked at all. The oil level is fine. It is still overheating the oil. Anyone already have something like this happen that could maybe save me some labor dollars when the mechanic comes over to check it out? I am hoping that it is something simple. Thanks Mike

Re: 525 EFI overheating the oil?
 

How is the oil pressure?

Re: 525 EFI overheating the oil?
 

Around 30 psi at 4000 rpm. The other motors are running around 40 psi at the same rpm.

Re: 525 EFI overheating the oil?
 

providing there is nothing major mechanically going on change the oil filter as when it gets clogged the oil goes through the by-pass and then does not pass by the cooler.

Re: 525 EFI overheating the oil?
 

I did not know that. I will do that next, hopefully that is all it is. Thank you Mike

Re: 525 EFI overheating the oil?
 

It might very well be what asg said. However, my experience with triple diesels is that the center engine will always run hotter and will generally use more oil. The center engine seems to be constantly experiencing a higher load factor.

Re: 525 EFI overheating the oil?
 

Just had the problem that asg said. Changed filter and that fixed the problem.

Re: 525 EFI overheating the oil?
 

Well I guess I will get a filter on Monday and try it. That would be great if a new filter would fix it.

Re: 525 EFI overheating the oil?
 

if you know for a fact that the oil is getting to hot then disregard, but have you checked your senders and guage wires?

Re: 525 EFI overheating the oil?
 

What temp are you running? My buddy's center motor runs the oil 10-20 hotter, but still never goes much over 220. If it was a salt water boat you may have deposits in the oil cooler that are restricting heat transfer, a good soak in CLR or muriatic acid should clear that right up.

Re: 525 EFI overheating the oil?
 

It is running 100 degrees hotter than the other two. I will change the filter next and if that does not do it try acid washing the cooler.

Re: 525 EFI overheating the oil?
 

we just had a triple 525 fountain in the shop w/ the same problem,found the problem in the oil t-stat housing

Re: 525 EFI overheating the oil?
 

This is also on a triple 47 Fountain.(center motor) So the t-stat housing fixed the problem. Thanks for the info, I figured someone else has had this problem and could point me in the right direction. Thanks MIke

Re: 525 EFI overheating the oil?
 

we found the oil t-stat piston binding in the housing,not allowing the oil t-stat to open all the way

Re: 525 EFI overheating the oil?
 

I'd go with dollerparts, I don't think scale would cause 100 degree differences. Thermostat is a good bet at that temp (no oil flow through cooler at all).

Re: 525 EFI overheating the oil?
 

Thanks Art. We just changed it out and put in new oil and filter and the problem is fixed. I noticed that the new one has a extra washer in there that will keep the hole open about a 1/4 of an inch. The one that came off the motor did not have this washer. I am assuming this is so if the piston gets stuck it will still let some oil go to the cooler. Also the mercury filter I got is white? But this is the correct part number according to the local dealer. Does the black one only come on the motor from the factory or do you sell black mercury racing filters? Thanks Mike

Re: 525 EFI overheating the oil?
 

mike,they come in both colors 16595q is white and 16595t1 for black same $ for either art

Re: 525 EFI overheating the oil?
 

So was it the thermostat or the oil filter?

Re: 525 EFI overheating the oil?
 

Those center engines on triples from the discussions I have seen here are always finiky with water feeding, prop wash and so forth. Check the pick up and try to sdjust that if your not feeding from the drive.

Re: 525 EFI overheating the oil?
 

Combo of both. Before the middle engine was pinning the 340 temp gauge. Changed the t-stat and ran it. It went to 260 and the PSI was down 20 from the other two motors. So we figured the oil must have boiled and separated. Changed the oil and filter and they all now run around 220 degrees and the same PSI at all rpms.

Re: 525 EFI overheating the oil?
 

Do you have the black ones in stock? If so I want to buy 3 of them. Mike

Re: 525 EFI overheating the oil?
 

Driven, you going out on Saturday? Let me know and I will bring the camera and lens'. Should be a nice day out.

:D

Re: 525 EFI overheating the oil?
 

Gotta work this weekend. I will be going out next week Tuesday, Wednesday and Thursday if you want to take some pictures. Mike

Re: 525 EFI overheating the oil?
 

Does a stock 500efi come with oil thermostats?????


340 thats hot :eek:

Re: 525 EFI overheating the oil?
 

Mike, I will be out of town on biz in W. Palm, Lauderdale and Miami next week. I will be working at home most of the following week. Catch you then!
Mike C