so i bought a reproduction radiator for my 1954 235 and it seems to be cooling fine because it hasnt moved yet and i only have a small fan pushing air through, but when it ran its first minute, this weird fibery cotton ball like crud appeared in the top tank. idk what is or where it came from but its clogged up quite a few of the cores and the last time i tried to clean it out it seemed like even more appeared. has this happened to anyone else and what would yall recommend i do? ive already taken it off and pushed water backwards through it but apparently it didnt work.
Owner of the most temperamental 1951 3100 in existence
It would seem as though, after it was made and possibly in storage in some warehouse, that some little 4 legged creature moved in. If you think it is not flowing them only one thing to do and to be safe, take it to a radiator shop that can test the flow and or pull the top and rod it out. One thing we so not want with our old trucks is running hot in traffic, parades and just plain hot weather. Bite the bullet now.
certainly wouldnt hurt to do something now then deal with a blown head gasket later. that would make sense because it didn't have any seals on it. ill probably just pull the top.
Owner of the most temperamental 1951 3100 in existence
So I had something like this happen! Did you ensure that there were no shipping peanuts in the radiator hoses when you put them on? I found one in my upper hose come floating out as I was filling radiator and started to come up to temp. I pulled upper hose and found a few more. Not sure how they got there, but might be worth a look!
i did check the thing pretty thorough before i put it on. what i might try is adding a 50/50 mix of water and draino or some solvent that might dissolve this stuff without damaging the paint metal or the copper radiator. ill test it out by setting some of the sludge i harvested in it and see if it dissolves it. ill also set some on the valve cover to see if itll hurt the paint and set some on a old copper plate i have. ive also removed the thermostat because its florida and it was also completely plugged with the stuff. im sure ill find something. it seems like a artificial fiber and while im at it im gonna clean the whole cooling system because when it got rebuilt for some reason it got extremely dirty in the system and theres a crapload of what i think was old rust and alot of machine oil to keep the head from rusting (the inside of it wasnt painted). i also read up that in the heads of these 235's there is these water jets or something of that nature that pass water up through the head. is this true and if so ill have to flush the cooling system backwards because theyd be clogged.
Owner of the most temperamental 1951 3100 in existence
hi Mr. Dane, if i have to tackle this problem these are things i would consider. if you can isolate some of this material i suggest you do a burn test on it with a butane lighter natural fibers will usually burn to dry ash when you smear it between your fingers, and artificial fibers will melt. this test is used in textile industry to detect silk and cotton blends, pure silk and cotton burns to dry ash with no melting.
draino will not harm any of the original engine parts however it will be ineffective against any artificial plastic based fibers so if your fibers melt you can skip trying draino as it's already a no go.
pure gasoline may melt some plastic fibers away, but then you will have to be a concerned about the water pump seals and lubrication.
acetone will absolutely damage nearly all plastics and rubbers, so if you are flushing only a radiator then that would be okay, but acetone will destroy your water pump. acetone won't do much to natural fibers like silk or cotton.
i would not recommend any acids for this application as acids would be less effective than the aforementioned chemicals and the coolant system has parts that are susceptible to most of the usual candidate acids at various places. -s
thank you for the advice i will go try that right now. when i felt one clump after it dried up they felt fairly real but because there so gunked up it didnt feel right. its good to have friends in high places!
Owner of the most temperamental 1951 3100 in existence
"because when it got rebuilt for some reason it got extremely dirty in the system and theres a crapload of what i think was old rust and alot of machine oil to keep the head from rusting (the inside of it wasnt painted)."
....maybe a mouse built a nest in the engine before you picked it up???? Was all the holes plugged? maybe not the radiator's fault?? Just curious. Makes sense, as you mentioned, to flush the entire system.
i did the burn test and sure enough it caught on fire and kinda evaporated/formed ash. so draino it is i guess. should i do a 50/50 mix of it or just straight draino? i know its expensive so id like to doa 50/50 mix but idk how well that would work..
Owner of the most temperamental 1951 3100 in existence
update: today i completely tore down the cooling system. i took the radiator off and the thermostat is always out because its 85-90 on the daily here. i set the radiator with the flow holes pointing upward, i put the cap on and filled the entire thing with straight draino. i then took the garden hose stuck it in the top hose and backflushed the engine for about 1 hour. there mustve been 10 cotton balls worth of this crud that kept washing out. in the end of this flush the water ran completely clear. i then proceeded to flush the radiator in reverse and every last ounce of that crap came right out didnt even have to rod it out. i put everything back together after completely drying it with a blow dryer, engine and radiator, and plugged it all back together filled it up with the dirty coolant that i filtered using coffee filters (super slow and its still a little dirty but it made a huge difference) and now instead of running at about 190-200 it runs at a steady 150-160. in short, i super duper over crazy cleaned this thing out and it definitely payed off. i also made sure to evaporate that small bit of water that resonates below the water pump in that space. im running the GM orange coolant in it. i dont think it was pre mixed but i added about half a gallon to the two+ gallons that it already held a little of that coolant did flush out when i ran water through it backwards, i tried to stop it but it had already gone to the dirt.. i did however flush that area for about another hour with water so hopefully i helped it... (the water after the radiator went clean)
Owner of the most temperamental 1951 3100 in existence
well ill certainly take this to heart. is there a rust inhibitor additive that i can perhaps add to distilled water? that is what im eventually going to do but i need to find the rust stuff.. actually scratch that ill just go get some green stuff.
Last edited by Mr. Dane; 10/11/201810:35 AM.
Owner of the most temperamental 1951 3100 in existence
If you are running 150-160, you are not allowing the engine to fully warm up to burn off water in the oil, etc. it would be better to replace the t'stat for more efficiency.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires. '47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle. '54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed. '55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
I don’t have one in there mainly because it’s Florida and it’s usually hot as balls here. I’ve asked around and all my classic car buddies say it should be fine.
Owner of the most temperamental 1951 3100 in existence