radiator hoses

[three80three]

Whats up everybody I just recently gkt this motor and the cam had a worn lobe on it which made the truck backfire from the carb I ordered a cam installation went smooth, I dropped the motor in my 84 scottsdale swb and found that the flywheel was cracked so I changed it now what im wondering is why the upper radiator hose is s ok tight is supposed to be that way or could my thermostat be stuck in the closed position? Im thinking about taking the thermostat completely out does anyone have any suggestions?

[brad_man_72]

Don't run without a thermostat.
If you're overheating/boiling coolant and the upper hose is cold, the thermostat isn't opening. Replace thermostat.

[GASoline71]

Did you tear down the engine after the cam wiped out? There will be massive amounts of metal particles embedded in the main, rod and cam bearings. The oil pump will be trashed and the engine oil galleries need to be completely flushed out.

Gary

[three80three]

All of that has been clean out there wasn't a large amount in the motor what im trying to determine is if the top radiator hose supposed to have that much pressure on it

[donut]

Top hose will only have as much pressure as the radiator cap will allow. Kinda like a pressure relief for the cooling system.

[cableguy0]

If the upper hose is swollen and looks like it may explode it could be a blown head gasket or cracked head allowing cylinder pressure into the cooling system. A bad thermostat will stop water from flowing through the upper hose at all.
On an engine that wipes a cam its not the metal you see that causes a problem its the metal that winds up embedded in the bearings.

[three80three]

The cam is fine thats no longer my problem the motor has been installed in the truck and runs fine I drove the the truck on the highway about 45 minutes away to visit a friend and noticed that the temp was a lil above 210*. The truck drove fine along the way once I got off the highway and stopped at the light I noticed the temp the radiator is holding there are no leaks I have a brand new flex fan on it I thought the thermostat may be sticking so I took it out before coming back home and it still about 210 is that normal? I have a 96 suburban and it never runs above 190,195

[haysonj]

Originally Posted by three80three

The cam is fine thats no longer my problem the motor has been installed in the truck and runs fine I drove the the truck on the highway about 45 minutes away to visit a friend and noticed that the temp was a lil above 210*. The truck drove fine along the way once I got off the highway and stopped at the light I noticed the temp the radiator is holding there are no leaks I have a brand new flex fan on it I thought the thermostat may be sticking so I took it out before coming back home and it still about 210 is that normal? I have a 96 suburban and it never runs above 190,195

Your Suburban has a 195 degree thermastat and I would suggest you run a 195 degree in your truck. If you don't have one the water will go through the radiator so fast is does not have time to transfer the heat out. I have a 195 in mine and it will only go up to 210 when pulling hills in 100 degree heat.

[three80three]

I get what you are saying but the funny part is I drove my suburban to Gatlinburg Tennessee 4hours away from where I live up and down hills and through backed up traffic then stop and go now the funniest thing is I have a radiator out of a truck that had a 4.3 in and still my suburban runs no hotter than 195 with a 195 thermostat

[storm9c1]

If you are running hot, change the thermostat. Ditch the flex fan for a correct 6 or 7-blade fan with a thermal clutch. Also check timing, too retarded? Check carb for lean. Make sure no air is trapped. All of these things will cause extra heat.

Not really sure what your problem is since you didn't explain the symptoms much. Any overflow from the cap? Do you hear any boiling? Are both the upper and lower hoses the same stiffness? Does touching the radiator tank burn your finger or read above 210 with an infrared gun? Lots more diagnosis needs done.

[three80three]

When you say the timing may be to retarded explain that a lil more for me because I was under the impression that the timing was fine because when I hit the key it turns right over no hesitation BUT it does take a minute to warm up it ru s real sluggish for about 2 or 3 minutes then it will start to idle just fine. Should I turn the timing up on it or down I went the auto parts store and I promise it seemed like there was a drought on 195 thermostats so I bout what they had a160 and drilled a few small Holes in it now its running close to 210 but not quite on it what should I do? I can't get another fan til next week so whats the next best thing?

[three80three]

Theres no boiling no overflow and I haven't checked the bottom hose but the top one is stiff

[storm9c1]

Before we get too crazy, I would think if the pressure is too high, the cap would allow some overflow. What PSI cap is on there? The cap controls the amount of pressure in the system. If it is unknown, just replace it. It's cheap.

There would have been no need to drill holes in a 160 stat. Maybe a single tiny one to relieve trapped air. But that's all. I do think you are running a little hot due to some other influence. And the things already mentioned could affect that. Check your timing at idle with a timing light! For example, timing set to 2 degrees BTDC (too little initial advance) will start right up but will run like crap and have no power and will produce extra heat. Did you say what type if ignition you had? HEI? If so, then it should be set to at least 8 degrees advanced.

Also a carb running lean cause excess heat. Make sure the choke is working on the carb. Make sure it is opening -- or wire it open -- and see if the problems still persists. Sometimes it could also be dirty jets. Or the carb is just jetted or metered too lean to begin with. There are a ton of factors here. Unfortunately we gotta start somewhere and work through the list.

[three80three]

I totally agree with you on the timing because upon starting it, it will crank right up but im lacking serious power and when it cranks the gas is burning very rich and takes a minute warm up. I'm not sure what cap is on it whats the best one to have so that I dont get very much pressure? And im not sure u ow work a timing light all I know is to turn the distributor housing what should I be listening for I know how to adjust the carbs idle mixture it's just the timing that I am confused about and what pressure cap I should have .

[storm9c1]

I'd go to the parts store and get whatever the stock cap is for that truck. Should be like 16psi. Make sure the overflow goes somewhere and is not capped off or plugged.

Timing by ear will get you home. But now that you are having problems, I do suggest finding someone with a timing light and let them help you. Or buy one yourself. If that's a HEI setup (coil on cap) then you want at least 8 degrees at idle on a stock engine, some engines like 12-14 degrees (or more depending on cam). Engines with older points ignitions may want less.

Same goes with adjusting the carb -- best results are achieved with a vacuum gauge. You would hook it up and then adjust the idle mix screws to get highest vacuum readings at idle (on a warmed up engine). But if you are running hot while cruising, it won't be your idle mixture. It would be jets or metering rods (depends on carb).

I also don't know if you mentioned the year of this rig, carb type, ignition type, is engine stock or built? That all matters!

[three80three]

I think I'm getting close to where its supposed to be by just loosening the distributor bolt just enough to turn the distributor very slowly it's still cranking on the first turn and it did have a lil gas smell to like it was burning rich but that's gone and I pulled out onthe street a foot breaked it and it spinned a tire with ease then afterwards I pulled back in the yard and let it run while I went and made me a sandwich and the temp needle is resting on the line in between 100 and 210and it's been running for quite some time now.