Page 1 of 1

Oil temp issue

Posted: Wed Nov 01, 2017 8:13 pm
by rowdy1
I have a Cont. 520. It has the vernatherm valve in it and a Hayden 1260 oil cooler on it, the temp sender is in the block below where the oil lines come out. Its a sand cast motor. The problem I have is that the oil temp. It warms up slowly (according to the gauge). However after 150 deg. it goes straight to 190 and then on up. This is normal running, I don't run it hard, rarely over 2300rpms. In fact the boat cruises around 1900. Can I take the vernatherm out of the motor? Oil pressure is around 40psi.
Any thoughts?

Re: Oil temp issue

Posted: Thu Nov 02, 2017 12:23 pm
by fjdrill
If it was me I'd check my Temp with a known relibale oil temp gauge first. I've chased my tail with an 0-540 on an airplane-gets expensive quick

Re: Oil temp issue

Posted: Thu Nov 02, 2017 3:06 pm
by rowdy1
Two different hulls, two different gauges, same issue. I forgot to mention that in the original post.

Re: Oil temp issue

Posted: Wed Nov 08, 2017 7:33 pm
by rowdy1
OK, I did a test today. I ran the boat on the trailer at 1900rpms and monitored EGTs and oil temp with my temp gun. It took 21 minutes to go from 0 to 230 degrees on the oil temp. It never got more that 135 deg, on the inlet or outlet side of the oil cooler. There is definitely no flow to the oil cooler. Before anyone asks, I did fill the oil cooler with oil, in fact I took the lines loose at the block, held them up and poured oil into one until it finally ran out the other. Vernatham Valve?

Re: Oil temp issue

Posted: Wed Nov 08, 2017 8:05 pm
by kwanjangnihm
older threads mention oil cooler bypass being dirty or clogged not allowing oil to flow to cooler

has this been checked?

Re: Oil temp issue

Posted: Thu Nov 09, 2017 1:34 pm
by rowdy1
That's todays project, I am going to pull the vernatherm out. (if I can find a thin wall 1 1/2 socket)

Re: Oil temp issue

Posted: Sun Nov 12, 2017 7:24 pm
by rowdy1
Update:
I removed the valve only to find there was no "guts" in it. The block had been tapped and a plug installed. I removed the plug, installed a valve and ran the boat on the trailer again. Oil temp got up to 190 deg., valve opened, the cooler was 190 on the inlet side, 145 on the outlet.
I thought everything was fixed!

I took the boat out and ran it this afternoon. The boat ran fine, the oil temp climbed to around 180 and then just kept going. I again shut it off at 230 deg. It took about 30 minutes. Again, both sides of the cooler lines were luke warm. The oil pressure is 40 psi, even at 230deg.

Is it possible that there is an internal leak that is letting air into the oil system?

WHAT THE HELL IS GOING ON?

Re: Oil temp issue

Posted: Mon Nov 13, 2017 8:54 am
by John Fenner
You have a blowby problem, ring lands are worn on the pistons, and or egg shaped cylinder bores, I would suggest a proper leak down test.

Re: Oil temp issue

Posted: Mon Nov 13, 2017 10:08 am
by rowdy1
Fresh motor, still on mineral oil w/ about 25 hours. Just stopped consuming oil. Little to no blow by.

Re: Oil temp issue

Posted: Mon Nov 13, 2017 12:34 pm
by StanleyAirboats
YOU HAFT TO PUT THE PLUG BACK IN THAT FORCES THE OIL TO GO THROUGH THE OIL COOLER.

Re: Oil temp issue

Posted: Mon Nov 13, 2017 12:37 pm
by StanleyAirboats
THOSE MOTORS RUN AT 190 TO 210

Re: Oil temp issue

Posted: Tue Nov 14, 2017 8:33 pm
by rowdy1
I'm asking this as a question, I don't want this to come off as smart ass.
If the plug is in the motor, how is it possible to not have oil moving thru the cooler? The original problem is that there seemed to be no flow. When the oil temp was 230, both sides of the cooler read 135- 140. That's is why I was sure there was a vernatherm problem. Is there any possible way for that to happen? Im lost

Re: Oil temp issue

Posted: Wed Nov 15, 2017 5:15 am
by kwanjangnihm

Re: Oil temp issue

Posted: Wed Nov 15, 2017 8:27 am
by StanleyAirboats
IF THE PLUG IS IN THE RIGHT PLACE IT HAS TO FLOW THROUGH THE OIL COOLER IT SHOULD BE TAPPED BETWEEN THE TWO LINES IF THAT IS CORRECT IT IS SOMTHING ELSE CHECK YOUR FILTER SCREEN IN THE OIL PUMP TO MAKE SURE IT IS CLEAN. TRYING TO HELP CALL WITH ANY QEUSTIONS BEN STANLEY. 407-427-0650

Re: Oil temp issue

Posted: Wed Nov 15, 2017 9:03 am
by rowdy1
Yes Sir, Thank you. The plug is in the passageway, I have even used a depth gauge to make sure it is not in to far, thereby blocking off the outlet. I am in the process of threading the vernatherm cap and installing a temporary oil pressure gauge to check the pressure. I am wondering if there is a plug left out of the block somewhere that would allow oil to bypass the cooler.

Re: Oil temp issue

Posted: Wed Nov 15, 2017 9:30 am
by StanleyAirboats
there is a plug in the front under the cam gear in the lifter vally location that could be possible.I WOULD NOT THINK YOU WOULD HAVE 40 PSI . OF OIL PRESSURE .

Re: Oil temp issue

Posted: Wed Nov 15, 2017 9:40 am
by StanleyAirboats
WHERE DO YOU HAVE YOUR OIL PRESSURE COMING FROM

Re: Oil temp issue

Posted: Wed Nov 15, 2017 4:56 pm
by rowdy1
Right side of the engine, under the center cylinder. (Looking at it from the prop)