Running Hot
Printed From: CorrectCraftFan.com
Category: Repairs and Maintenance
Forum Name: Engine Repair
Forum Discription: Engine problems and solutions
URL: http://www.CorrectCraftFan.com/forum/forum_posts.asp?TID=2079
Printed Date: November-23-2024 at 3:41am
Topic: Running Hot
Posted By: Lefty
Subject: Running Hot
Date Posted: July-15-2005 at 4:03pm
| Our 89, 2001 with a 351 PCM (530 hrs) started running hot last week. I shut her down after the gauge got to 200. After replacing the impellor and the thermostat she still runs warm at 180 (usually ran at 160). Any suggestions? |
Replies:
Posted By: skyhawkflyer
Date Posted: July-15-2005 at 4:47pm
|
Is your strainer clean? Did you stick in a 140 or 160 degree stat?. ------------- |
Posted By: mackwrench
Date Posted: July-15-2005 at 5:17pm
|
Make sure you have no restriction in the exhaust, rust inside manifods, stopped up muffler etc..., all the water in the world won't cool it if it can't get out though the exhaust. ------------- NO LONGER A MEMBER |
Posted By: David F
Date Posted: July-15-2005 at 5:22pm
|
If the water cannot get out of the exhaust, neither can the exhaust gases and the engine thereby would not run at all.
160 - 180 is normal range. Check the thermostat temperature set point. |
Posted By: skyhawkflyer
Date Posted: July-15-2005 at 6:09pm
|
If you stuck in an automotive type stat those are different, usually 180 degree. Must be marine part. ------------- |
Posted By: Lefty
Date Posted: July-15-2005 at 11:05pm
| The thermo is a 140 marine. All strainers are clean. How do I check for rust in the exhaust manifold without a tear down. The boat runs strong other than the overheat. |
Posted By: Tim D
Date Posted: July-19-2005 at 8:00pm
|
I would replace the sending unit, just to rule out if it is really running hotter than before. ------------- Tim D |
Posted By: Guests
Date Posted: July-20-2005 at 2:03am
Completely incorrect. The manifold is jacketed. Water runs inside the jackets and exhaust goes in the center. Only at the end of the elbows do exhaust and water mix. You can have water blocked and still get plenty of exhaust through. |
skyhawkflyer wrote:Posted By: Guests
Date Posted: July-20-2005 at 2:04am
| In post above, meant to quote David F, not Skyhawk. ^^^ |
Posted By: David F
Date Posted: July-20-2005 at 12:35pm
| Yes, you are absolutely correct and I agree. |
Posted By: Guests
Date Posted: July-20-2005 at 10:54pm
When I removed the winterizing plug from the exhaust manifold I did get a significant amount of scale and rust out. After doing that the water runs clear and there seems to be the normal amount coming out of the exhaust. An other suggestions? |
Posted By: 66altyllskier
Date Posted: August-08-2005 at 1:45am
| Got a 66 Al tyll skier w/the same problem. Changed the impellers & thermostat, still jumpin up to 220. pulled the thermostat out and still getting all the way up, when I back her down to 1k rpm she cools right down. will update when I pin it down. |
Posted By: HOLESHOT
Date Posted: August-08-2005 at 2:31pm
|
my 82 did the same thing and it was the sending unit ------------- IF IT HAS A SPARKPLUG I CAN FIX IT |
Posted By: '72 mustang
Date Posted: August-08-2005 at 3:08pm
|
My engine was getting up to 200 at speed and would cool back down to 160 at 1k rpm. The trans oil cooler was clogged. ------------- 72 CC mustang |
Posted By: 66altyllskier
Date Posted: August-09-2005 at 11:20am
I'll take a look at that this week, it would be nice if I could find the fix without pulling her out of the water, thanks 72. Also, the water intakes in the bottom of the boat, is there an additional screen after the stainless looking water intake w/the slots in it or is that it? Can't say I've ever pulled them off the bottom of the boat. thanks Bill |
Posted By: David F
Date Posted: August-09-2005 at 12:51pm
|
The trans cooler should be above the normal water line while the boat is at rest. Therefore, if you disconnect the water intake hose at the cooler, water should not enter the boat. The water will seek its own level in the hose which would be below the cooler. Just make sure you keep the end of the hose above the water line and not let it fall down into the bilge.
There is not a screen on the inlet, just the grille. |
Posted By: 73skier
Date Posted: August-10-2005 at 12:03am
| would warmer water make any change in temps.My 73 goes from 160-180 but if I'm in the warmer part of the lake it might go to close to 200 see i have a power plant on my lake so it has hot spots. water temps could be close to 120 is that normal? |
Posted By: '72 mustang
Date Posted: August-10-2005 at 5:03pm
|
Hope it works out for you. I either overheated it and didnt catch it soon enough or it was already done before I bought it in July but I ended up with blown head gaskets. Finally got it back together and it fired right up for me last night. Going for a test run after work today. It sure felt good to hear the engine start up after having it sit in my garage for a month. Anyways I would hate to see anyone go through what I did for something so simple. Newbie mistake on my part, didnt know to check for something like that. ------------- 72 CC mustang |
Posted By: Lefty
Date Posted: August-14-2005 at 1:05am
| Turns out my problem was a bad ground to the dash. I ran a new ground back to the block and in doing so found that the original was badly corroded. |
Posted By: 66altyllskier
Date Posted: August-22-2005 at 7:06pm
| Thanks '72 mustang, I pulled the hose off the tranny cooler and sure enough found quite a few chunks of impeller. She seems to hold steady at 200 while running flat out, better, but not perfect. Before we couldn't get 2 miles w/o having to back down to idle. Now we can cruise without a problem, I actually got to ski Saturday! Hopefully things still look good when i drop the thermostat back in. The engine's 39 years old so she may have a bit of buildup. Probably save me a bunch of trouble, thanks again, and glad to hear you're back up and running. |