pdqmovie Posted October 28, 2012 Share Posted October 28, 2012 Hi there , I have a 1987 Toyota dolphin motorhome, 4 cyl. I have had this for about 5 yeas now with no poblems. One day it got very hot with the temperature guage going up while climbing a hill but never completely overheated. I took it to my mechanic to have a new thermostat put in. I went out for a trip and it still did the same thing. I then changed the radiator to a new one, 3 core. It stayed on 1 / 4 on the temp but on the free way, where there was no stopping or slowing down, I am at a constant speed of 55 to 65, the temp goes up to 3 / 4 of the way again. This was not up a hill or anything, just driving flat on the freeway. When I got off the freeway to a stop, the temp went down to the 1 / 4 mark again. The weather was not real hot, just warm. This is confusing to me as I am not sure where to go next, get a new fan clutch, maybe a new water pump, or have the engine flushed out. I just need some help on what to do next. Thanks Quote Link to comment Share on other sites More sharing options...
pdqmovie Posted October 29, 2012 Author Share Posted October 29, 2012 here a pic Quote Link to comment Share on other sites More sharing options...
Maineah Posted October 29, 2012 Share Posted October 29, 2012 You need to find some one you can trust to have a look, throwing parts at some thing to fix a problem can get expensive fast. Is the radiator plugged up? is the fan clutch bad? maybe there is a head gasket problem and the list goes on. From here it just a guess many good suggestions maybe but with out hands on it's really hard. Quote Link to comment Share on other sites More sharing options...
Maineah Posted October 29, 2012 Share Posted October 29, 2012 Is the temp gauge really telling the truth? A good shop should be able to tell you. The picture shows less then hot the red zone is hot but it may show more then you are used to so find out how hot it really is and go from there. Quote Link to comment Share on other sites More sharing options...
centralman Posted October 29, 2012 Share Posted October 29, 2012 I had a cooling problem awhile back, please check out this topic to see if it could be of some use to you: http://toyotamotorhome.org/forums/index.php?showtopic=2907&hl=%2Bcooling+%2Bdown+%2Bthe+%2B22re Quote Link to comment Share on other sites More sharing options...
waiter Posted October 29, 2012 Share Posted October 29, 2012 If you've been driving it for 5 years, then you should have a good feel for whats normal for your truck. On mine, if there is any load on the engine (uphill, headwind, speeds greater than 55-60, Air temp > 75-80 deg) I will see the temperature go up to the 3/4 mark, similar to what I see in your photo. In your case - Is the quality of the new three core better than the your original 2 core. Make sure the radiator level is OK, The 4 cylinder should draw coolant into the radiator when it cools down, pop the radiator cap when its cool and make sure it full to the brim. I assume you put a new cap on when you replaced the radiator. John Mc 88 Dolphin 4 Auto Quote Link to comment Share on other sites More sharing options...
centralman Posted October 29, 2012 Share Posted October 29, 2012 Oh since we are discussing the engine coolant temperature here my MH's temp will go all the way down to "C" when it's going a long stretch of downhill (for example, I-5 at Siskiyou Summit), then the temperature will get back to normal once it's on level ground, does this happen to you guys? Quote Link to comment Share on other sites More sharing options...
5Toyota Posted November 1, 2012 Share Posted November 1, 2012 IF THE FAN CLUTCH SLIPS CAN RUN ABOVE NORMAL I HAD A 20 R CAR THAT WOULD NOT HEAT UP GOOD THE FAN CLUTCH WAS FROZEN SOLID STAYED FULLY LOCKED ALL TIME Quote Link to comment Share on other sites More sharing options...
waiter Posted November 1, 2012 Share Posted November 1, 2012 Centralman, the Thermostat should keep this from happening. if the coolant temp gets to low, the thermostat should close down an restrict water to the radiator. On most cooling systems, the passenger heater bypasses the thermostat, but its not that much that would cause this (I would think). As 5Toyota - a stuck fan clutch could also aggravate this problem (fan running all the time) John Mc 88 Dolphin 4 Auto Quote Link to comment Share on other sites More sharing options...
centralman Posted November 1, 2012 Share Posted November 1, 2012 Centralman, the Thermostat should keep this from happening. if the coolant temp gets to low, the thermostat should close down an restrict water to the radiator. On most cooling systems, the passenger heater bypasses the thermostat, but its not that much that would cause this (I would think). As 5Toyota - a stuck fan clutch could also aggravate this problem (fan running all the time) John Mc 88 Dolphin 4 Auto Hi John, Now I kind of know why. When I was trying to solve my engine running hot problem, first I tried to replace the existing thermostat (which is a relatively new one) with the Toyota 2-stage thermostat: http://4crawler.com/4x4//CheapTricks/index.shtml#Thermostat When that didn't work I was thinking, hmmm, maybe even the 2 stage thermostat isn't quite good enough, and someone even advised me to remove the thermostat altogether, I then tried the advise mentioned on the link to put back my old thermostat and drilled a couple of holes on them to act as bypass. Maybe that's the reason why this is happening, and eventually even that didn't work and in the end I replaced the fuel injectors and problem solved. Thanks John & 5Toyota for their comments. Quote Link to comment Share on other sites More sharing options...
ILIA Posted November 2, 2012 Share Posted November 2, 2012 Is it the original water pump? How often was that coolant flushed? My guess is that the blades on the pump may have broken and the pump can no longer provide sufficient cooling at higher temps. Those pumps aren't that tough to switch out. I would strongly consider it if your coolant was rarely flushed and it is the original pump. Quote Link to comment Share on other sites More sharing options...
pdqmovie Posted November 2, 2012 Author Share Posted November 2, 2012 Hi everyone thanks for the input i think i go with the belts being all replace and fan clutch replace also the quote i got was 240.00 to do all the belts and replace fan clutch and labor is 240.00 is this a good price ?? Quote Link to comment Share on other sites More sharing options...
5Toyota Posted November 3, 2012 Share Posted November 3, 2012 those fan clutches used to run 50 60 dollors i dont know anymore. Quote Link to comment Share on other sites More sharing options...
ILIA Posted November 3, 2012 Share Posted November 3, 2012 That's not gonna solve a thing, but should be replaced if old anyway. If your belts are intact and fan turns on already then replacing worn parts in that department won't make you run cooler. Quote Link to comment Share on other sites More sharing options...
pdqmovie Posted September 15, 2013 Author Share Posted September 15, 2013 how about a electric radiator fan for the front of the radiator to cool ?? Quote Link to comment Share on other sites More sharing options...
zero Posted September 15, 2013 Share Posted September 15, 2013 Hi everyone thanks for the input i think i go with the belts being all replace and fan clutch replace also the quote i got was 240.00 to do all the belts and replace fan clutch and labor is 240.00 is this a good price ?? News belts cost $2 to $3 each for a 2.4 Toyota. Three belts comes to less then $10. New fan cluch is $35. So - $200 labor to spend maybe one hour working on your rig? That's more then many lawyers charge!. I doubt your fan clutch has anything to do with it unless your machine has air-flow problems. Most "normal" vehicles don't need any fan at all when running down the highway. It's more for when stopped, driving slow, pulling a trailer up a hill, etc. But with a Toyota with an RV stuck onto it? it is not normal and not designed by Toyota, so who knows? Can't hurt to try one I guess. Quote Link to comment Share on other sites More sharing options...
zero Posted September 15, 2013 Share Posted September 15, 2013 Couple of questions? Have you checked to make sure the timing isn't too advanced? Also , any chance you've got too much anti-freeze in there? Antifreeze (ethylene glycol) is a poor remover of heat. Pure water in a engine gives better cooling but you need the coolant to prevent corrosion (and prevent freezing). Should never be more then 50% mix. Quote Link to comment Share on other sites More sharing options...
deadflo Posted June 10, 2017 Share Posted June 10, 2017 This is about the third thread I've found on overheating that ended with no resolution. Im having this exact same problem in my new rig, here is the thread if anyone has any new ideas, but it sounds like an all too common problem that no one is solving.Here is my thread on this issue. Sorry to say, Im disappointed I ever bought this rig. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.