CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

overheating suggestions

75starter

Registered Member
Joined
Nov 25, 2007
Posts
23
Reaction score
0
Location
chico
heres my question i just put a 305 in my 75 jimmy till i rebuild the og 350 but now the 305 is overheating even if i just drive to the store 2 miles away and back without stopping with the exeption of lights of course i re did all the gaskets exept the head gaskets before i put it in it came out of a truck that ran perfectly fine im not to mechanicly incline some one said it could be the timing how would i correct that what would i have to do to it advance/ retard ????
 
I would check the cooling system before I dove into any head gasket endeavor.

Fan belt tight?
Water pump working?
Cooling system full?
Thermostat opening?
Is there a fan shroud installed?
Clutch OK?
Lower radiator hose collapsing?
Radiator cap good and tight?
 
all new hoses
new thermostat 2nd one
yes fan shroud
no fan clutch new flexlite allways goin
new rad cap too running out of easy stuff
 
Make sure the thermostat is not upside down. The spring side of the tstat should be inside the block (down).
 
yeah i got both of those right but what do you guys know about the timing could it be so far off that it would run hot we never hit it with the timing light because it ran so good first fire we just adjusted the idle and left it
 
If it overheats while driving, it's not a fan issue.

You've either got a radiator problem, thermostat problem (if consistent whether the engine is loaded or unloaded, idle/driving, since the fan is not a factor short of the potentialshroud issue), or something with the engine itself.

Just because a radiator works with one engine, doesn't mean it will work with another. BTDT, there is abosolutely no way on this planet that can tell you if your radiator is working efficiently except flow testing. (you can try with an IR thermostat, but that still doesn't tell you how it works while you are moving)
 
heres somthing new i just drove it the other day and it overheated again but when i just went to check the coolant the radiator cap was covered in some rusty gunk the first radiator i had in it was the one that came in it and it was all rusty inside but i didnt notice till i ran it for a while thats when the overheating started so i switched to another one out of a 75 pickup same kind and not rusty could my engine just be full of crap and how would i flush it out clean it also looked like some one used radiator stop leak in it could it being full of gunk make it overheat ???
 
Stop leak can plug up the cores of the radiator, probably more likely if the bottom of the radiator is corroded and the tubes are narrower than they should be. I don't think it's supposed to gel up or anything, it's just a solid that fills in holes AFAIK.

Stop leak caused weird problems in one of my sisters cars.
 
what about all the rusty gunk it was almost like watery mud could it be clogin up the motor its not actually mud just alot of rusty crap or you think it cloged up the new radiator i put in how do i flush the whole cooling system when i took out my old thermostat to replace it it was all covered in the rusty stuff too
 
Not sure what the gunk was, stop leak stuff I saw looked (and stayed) in a flakey form.

I used the drain plugs on the block last time, but it was kind of a pain with water going everywhere. As a matter of fact, I had the engine running, hose going into the radiator fill, and the block drains open. Might not work to get crud out of the radiator, you might need to remove it for that.
 
You said the water pump is new. Is it the right pump for your belt system?. If the 305 was a serprntine belt engine. The water pump is reverse rotation. It wont work with standard V belts.
 
the new water pump is a long style just like the one that was on the og 350 same thng the guy had on the 305 before i bought it he never had a heat problem im gonna take it down have the cooling system flushed i dont think all the rusty gunk is doing it any good i gotta try and get my hands on a timing gun too dont feel like spendin 50 bucks just to check something that might not be the problem
 
There are two different long pumps and they are identical on the outside. One is standard rotation used with V-belts and the other is reverse rotation used with serp belt. The impeller inside the pump is what's different. Make sure that the pump you bought it matched with the type of belt system your rig has regardless of the year of either the truck or the engine.
 
i had an over heating problem with my blazer a while back and my heater didnt work. so what i ended up having to do is i got a new radiator and changed the heater core out and problem solved. 75 mph on the freeway pulling my atv on the trailer with the ac on no problems....
 
i dont know if my heater works its 107 degrees out right now or i would check i went to a radiator shop near my house he said it was around 250 for a new radiator and i still need a block flush or 280 to rod my old radiator and the flush included but for that money i think ill just start the build on my og 350 and just take more time worrying about the cooling system on that one
 
My burb was overheating while chugging through sand at slow speeds. The coolant never leaked and all the mechanical stuff was in working order. I drained some coolant out of the radiator and saw some pretty bad calcium build up. I ended up doing a muriatic acid flush per Ryoken's instructions and now it works a whole lot better. It will still overheat on rare occasions but not like it used to.
 
ryoken?? how do i find out how to do that acid flush also at the radiator shop the guy had pointed out that someone had used radiator stop leak before could that clog the wrong things up along with all the rusty gunk in there im just looking for a cheap easy sollution imagine that
 

Latest Posts

Top Bottom