I have a new rebuilt motor and transmission and just had a front end man check out everything. It is a 53 1/2 ton with a 1960 235 bored to a 261 equilavent. Taking it home from town, I had the speed clocked at what I thought was an acceptable speed and later found out I was going 70 (it felt like 55-60 to me). At 55 the temp stays about 205 with a 190 thermostat. At continued 70 it ran at 215 temp. Please advise your thoughts on acceptable temperature range and crusing speed. What is the max temp at which to operate? Thank you. kentc
Kent ; Those temps are fine , and they'll drop a bit as the engine breaks in . What you need to watch for is : the RPM's ~ connect up a tachometer (tune up device lying on the seat is fine) and go for a drive , figure out where 3,200 RPM in top gear is on your speedo and don't exceed that except for going up through the gears and you'll be fine . Remember to lay your hand on the front of the radiator with the engine warmed up and running to check for any cool spots ~ if you find any or it's not evenly hot side to side and cooler as you move your hand down , have the radiator " rodded out " by a competent shop who doesn't ask " what's that " when you take it in . If you've not yet done so , remove the thermostat and drill three 3/16" holes in the flat part , equally spaced around - this will help prevent flashing over to steam .
Engine speed I already had the radiator "rodded" out, so it should be ok. My speedometer does not work, but I will do the best I can. I had 2/3 of my pedal left going 70mph and it seemed to be in a no strain, but the temperature of 215 going 70 bothers me. I mechanic told me that up to 240 is ok, not sure I understand this one. I have 1.5 gallons of anti-freeze in the system. What about a front electric fan. I would think they cost very little and would not be noticable. Any suggestions? Thank you. kentc
I'm not sure about the older sixes, but when you bore the engines over they will run hotter than normal. It will run cooler after break in. For right now I think you are fine with 215. Anymore would bug me though.
Electric fans might do you some good in stop and go traffic, but they won't make any difference driving 70 down the highway.
Kent, I agree with Nate. (Why not?) Relax and enjoy your ride. Water boils at 220 degrees and freezes at 32 degrees. The whole reason you put antifreeze in is that it lowers the freezing point but it also raises the boiling point. Don't think that just because you are getting near 220 that it is a problem. As far as hurting the engine, I don't think so. I would give it time to break in some and see if it comes down any. If it doesn't then you just have an engine that likes it a little warmer. As long as you have good power and she is humming just enjoy. Gater
Er , Ah ~ ....Water actually boils @ 212° F last time I checked (that's why your early temperature gauge only goes that high) , adding pressure raises the boiling point by 3° F for each pound *but* you don't really want more than say 5 # pressure on these oldies . The % mixture of the coolant makes a lot of differance too , I always use a 40 % coolant and 60 % distilled water mix and yes , the distilled water makes a big differance as most tap water these days has WAY too many minerals in it for taste reasons , distilled water is cheap @ .99 CENTS the gallon in most supermarkets . Since you didn't mention the need to constantly top up the radiator , it's unlikely it's running too hot or overheating . As mentioned , boring always makes the engine run hotter , I personally stop @ .030" over and go looking for another block . Forget the speedo , hook up a tachometer , that's easy , just grab some old Zip Cord off the neightbor's junked TV set on the curb (Kerb for Neil) . O.K. ? relax , if it has 50 miles in it , it's allready time for the 1st. valve adjustment and HOT oil change . Dwell & timing can greatly affect heat too , it shouldn't have more than 32° BTDC (triangle mark stamped in flywheel) all in . As you can see , there's many experts on this board plus me , your freindly farm/junkyard/used car lot mechanic , all ready to give you good advice
Nate's right of course. I have killed more brain cells than I thought. Of course water boils at 212. I was right about 32 being the freezing point though, right? Thanks Nate, Gater
I love it! This is why I'm a 3rd grade teacher! I have a hard enough time with my guzzintas let alone berlin' points! Have I mentioned a g-r-e-a-t movie to watch is a new release, "The Fastest Indian" (I think...) With Sir Anthony Hopkins? Everyone who logs on here will love this movie! Scouts honor!
An electric fan is a good thing when you are stuck in traffic in this 100 degree Nebraska heat! I am thinking of heading north. I just can't take any more of this heat and humidity.... It fs up my hairdo.... anyone up North have a couch I can crash on... J/K Ciao -Jess
no no~ head South. We haven't had a day over 92 yet! 'course now that I wrote that... Hey KentC, what kind of back end do you have in your truck that you can roll along at 70mph with?
Rear End I do not know, the pickup sat at my fathers farm since 1961 (53 model), but I assume it is stock, the one that was put in all of them (having refinished it, I understand why he parked it). I was wondering that myself as Nate has previously stated that 60 was about norm cruising speed, and the mechanic told me to drive 55, as that was about the original intent - lubrication was not the best, so keep it down and it would last forever then. The mechanic employs my 14 year old son as a mechanic trainee this summer, so I thought it polite to listen to him. kentc
I understand that! I was just wondering, because the original torque tube twern't spose to do that. That's why Pat, CP, and others sell those ring gears for the back end. Yours is a T-tube? Thanks for the reply. Keep -er rollin!
Any farther north, you'll be in wild fire country and 100-plus degrees like they have up there in Rapid City right now!!! As for the radiator issue and all that, that sounds like an optimum temperature range. I had an S-10 with a 4.3L (264ci)and it seemed to always run at 210-215.... ALWAYS. I think my thermostat was a 190 too. Remember at 190 is when the engine begins to start pumping the water back into the radiator to cool... you'll always be running a tad hotter because it takes time to get cooler water back into the system. Redline on my truck was 260 degrees, and bottom end was 100, according to the guages. Since you are basically running a 261ci, I think the numbers are proportionate. By the way, THANK YOU NATE for the distilled water suggestion.... nothing worse than having to clean rust deposits out of a colling system and engine block because of impurities in the water!!!
I assume the 1.25 gal is in the radiator? the whole cooling system takes about 4 gallons. Just to mix it up, water boils at 100 deg C and freezes at 0 degs!!! Enjoy your truck and best wishes.... Put-PUt.
Rear Ends & Stuff.... Shirley has a real nice rear end... oops If you put skinny , tall tires on the back of your stock 3100 with 4:11 gears , a 216 will do maybe 50 ~ 55 without blowing up and a 235 should be able to make 55 as long as you want ~ the tall tires make this pissible . most folks don't take the time to search out the correct tires , going for good looking skins instead For God's sake ~ DON'T use imported water in your truck ! Anyone here have a radiator that has those crusty deposits on the tubes when you look inside , I know the real deal way to clean it out 100 % , works on those crappy tinfoil imported radiators too .
well???? Now, Nate~ you can't do that to us! Of COURSE we want to know. With the fill tube to my radiator being the way it is, I can't see what the inner part looks like.
