overheating is back

[zadam123]

well i thought i solved the problem of my overheating at the end of last summer by replacing my heater core but after driving all winter with absolutaly no problems the first nice day i took the car on a 1 hr drive and the overheating is back and the same symptoms are back . it overheats only in the daytime on hot days above 65. I drove tomy friends housefrom ny - nj during the day temp was around 65-70 i had to pull over on the 1hr drive 5 times to let the car cool down. I then drove home that night 5 hr later outside temp was now in the 50s with absolutaly no problems!

I still have no symptoms of a head gasket like oil mixed with antifreeze, smoke or a skip or loss of power just overheating when hot out.

If you havent read my other posts regarding this issue here is what was done to the car already trying to fix the problem, replaced the clutch fan, flushed the radiator and replaced the thermostat. I was told the water pump is pumping strong. I have talked to other mechanics and was told they highly doubt its a head gasket since there is no smoke or missfire but its hard to detect since this only happens on drives over 45 minutes on hot days.

[Kona-Vs]

I've had old radiator hoses soften up with heat and the suction from a good water pump collapse them

[Bob Barker]

I'm not sure on our trucks (just looked but didn't find anything), but on other cars there is a "high" spot on the cooling system that needs to be burped if the coolant has ever been drained, overheated and pushed into the overflow bottle, or gotten low and been refilled allowing air into the system. Basically what can happen is the air bubble get stuck in the water pump and it will not circulate the coolant through the engine.

[Triathlete]

Have you had the radiator checked? Could have a tube or two obstructed which would cause those symthoms.

[phines]

My VX wasn't making any smoke when I had that broken head bolt, so I wouldn't rule out the head gasket. Symptoms were very similar too.

[zadam123]

My VX wasn't making any smoke when I had that broken head bolt, so I wouldn't rule out the head gasket. Symptoms were very similar too.

can you see a broken head bolt if so where is it located?

[Bob Barker]

Pull off the valve covers and look inside.

[phines]

My VX and at least one other had the same head bolts break. I think it was the one closest to the front of the engine all the way on the passenger side.

[zadam123]

My VX and at least one other had the same head bolts break. I think it was the one closest to the front of the engine all the way on the passenger side.

can you see it from the top of the engine or do i have to look under the car?

[Y33TREKker]

can you see it from the top of the engine or do i have to look under the car?

Assuming that's what the problem with your VX is, head bolts are used to fasten the heads to the engine block. To see the tops of the head bolts, the valve covers have to be removed.

Maybe the members here who've mentioned having that particular front-passenger side head bolt break will provide specifics on which section of the bolts actually broke, but if they broke above the threads, it's possible that you'd be able to turn a broken bolt by hand once the valve cover was off.

Can't say that I have any other suggestions at the moment for what may be causing the overheating.

[zadam123]

Assuming that's what the problem with your VX is, head bolts are used to fasten the heads to the engine block. To see the tops of the head bolts, the valve covers have to be removed.

Maybe the members here who've mentioned having that particular front-passenger side head bolt break will provide specifics on which section of the bolts actually broke, but if they broke above the threads, it's possible that you'd be able to turn a broken bolt by hand once the valve cover was off.

Can't say that I have any other suggestions at the moment for what may be causing the overheating.

ok i an a novice so before i go crazy trying to figure out if this is the problem is there any way this could be the problem if all winter long i never overheated?

and also this pdf manual dont tell how to take off the valve cover is this hard to do? any writeups on it?

thanks

[phines]

I let the local garage track down the problem, so they took the valve covers off. I don't know how easy or difficult that is. This is where the broken head bolt was:



The bolt broke off right above the thread, so the valve cover and gravity was the only thing keeping the top of the bolt in there. If you have the same problem, you won't be able to fix it yourself. There aren't any bolt extractors that can reach it from the top side of the engine.

And yes, you could have had this problem all winter. I had the problem for several years before I finally figured out what it was and fixed it. I had to be very careful driving on warm days and it was never a problem on cold days unless I was towing a heavily loaded trailer.

[Y33TREKker]

ok i an a novice so before i go crazy trying to figure out if this is the problem is there any way this could be the problem if all winter long i never overheated?

and also this pdf manual dont tell how to take off the valve cover is this hard to do? any writeups on it?

thanks

I'd rather let one of the other members who have actually had those head bolts break weigh in as to whether it affected their VX's during the winter. However, if it was a broken head bolt causing the problems you're having, I'd personally imagine that kind of thing would probably cause problems regardless of ambient temps. Not sure about that though.

[Edited to add] - How was that for timing?

If you're looking at the .pdf file that's available from this site, try searching for "cylinder head cover LH" rather than "valve cover". It appears the "LH" side is the one for the passenger side, and as (good) luck would have it, that side doesn't seem to be as difficult as the driver side.

[Ldub]

I'm not sure on our trucks (just looked but didn't find anything), but on other cars there is a "high" spot on the cooling system that needs to be burped if the coolant has ever been drained, overheated and pushed into the overflow bottle, or gotten low and been refilled allowing air into the system. Basically what can happen is the air bubble get stuck in the water pump and it will not circulate the coolant through the engine.

FWIW...& it may not be much, A few yrs ago I read about a Rodeo or Trooper owner with similar problems, I believe it was over at Planet Isuzu.

He had to park his truck on some ramps, so that the nose was higher than the rear of the truck to "burp" all the air out of his cooling system.

Might be worth a shot...

[zadam123]

I let the local garage track down the problem, so they took the valve covers off. I don't know how easy or difficult that is. This is where the broken head bolt was:



The bolt broke off right above the thread, so the valve cover and gravity was the only thing keeping the top of the bolt in there. If you have the same problem, you won't be able to fix it yourself. There aren't any bolt extractors that can reach it from the top side of the engine.

And yes, you could have had this problem all winter. I had the problem for several years before I finally figured out what it was and fixed it. I had to be very careful driving on warm days and it was never a problem on cold days unless I was towing a heavily loaded trailer.

that sounds like exactaly what my problem is, thanks for the responce. I looked in the manual and am not going to even atttempt this job ,now i just have to find a mechanic to try listing to me to check this out. Just curious how much should i be charged to check this out?