just got a 49 streamliner . at least I think that's what its called . I'm a virgin .! never owned /drove a flat straight eight before . never road in one either , unless I was to young to remember . motor seems so smooth . gets hot very fast though . anyone know if these motors blow head gaskets on a normal basis . the hydro seems to work perfect , but cant go far until I can find a brake pedal . cant wait !i was reading the build on the 53 being built in ny . he said the block on his v.8 was pluged up with crud . anyone else have heating issues caused from crud . I would really like to keep the srt 8 , and not damage it. runs very good , if not for the heat . anyone ever split the exhaust on a straight eight . whats the best way to drop the rear ? blocks? front seems very low already . soft springs? looks like modern springs have fewer coils . do these front ends hold up well?? View attachment 3818389 View attachment 3818389 View attachment 3818390 View attachment 3818390
Neat old car. Cousins had one for a school car in the late 50's. Before needlessly tearing into the engine; and assuming the temp gauge is giving you an accurate temperature indication, the first thing I'd check is the thermostat to make sure it's opening. It can easily be checked in a pan on a stove. Next would be the radiator. With engine off, drain the coolant, disconnect the lower hose and run a garden hose into the radiator filler neck to check flow.
In their day they were known as a good reliable car capable of high speeds without overheating. You will need to check over the cooling system. Is the fan on? Is the thermostat working? Is the radiator clean? Sometimes blowing it out from behind with an air hose will remove 65 years worth of dirt and bugs. Is the cooling system clean? If you have an infrared thermometer you can find out a lot of interesting things. Use it to check the temp of the engine. The front and back should be the same within a few degrees. If the front is cool and the back is hot, it indicates the water distribution tube is rusted out. You can tell if the rad is plugged up if it has hot and cold spots. A simple way to clean the cooling system is to drain and refill with fresh water plus a bottle of CLR calcium lime and rust remover, or your favorite radiator flush. Drive around for 50 or 100 miles then drain and refill. Or follow the directions that come with the flushing compound. See if it helps, and if the coolant stays reasonably clean. If it is still muddy you may need a second treatment. If it has a blown head gasket you can find out by doing a compression test. If 2 adjacent cylinders have no compression there is where it is blown.
My dad bought a new '54 Pontiac eight. Last year of the straight eight. First car I ever drove. It cracked the block between an exhaust valve and the water jacket. That was in '58. So it didn't last long. It was well maintained and driven in an adult manner. Which was about all you could do with it. A leak down is always very informative way to find out where the leak is.
My 48 tended to run hot in traffic or when stopped. I didn't address it because I had a 389 ready to go into the car. I cut 1 and 1/2 coils from the old springs and used 3" or 4" blocks in the rear. [can't remember which] The rear never bottomed out but the front would. With the short tires, the car's front crossmember would occasionally hit raised areas on the hiways, especially the "eruptions" in the center of the lanes of I-80 in Indiana and Ohio. I'd pull over to let my brother o ut to close the hood....again. Do the fronts hold up well? Welp, I sold my 48 [same front end as a 49] to a buddy who had the car subframed with a front-steer Camaro. I use to borrow the car after the subframe surgery and it drove much better but it wasn't this low. Fact is: with any suspension design, if you position your car this low, it's going to occasionally rub, bottom out and scrape...just a fact of life for a really low car.
Every Pontiac straight 8 owner with overheating trouble should check the water distribution tube behind the pump. They rot away, causing the coolant to stop flowing rearward, which boils everything from the breach rearward. Splitting the manifold is a weird situation on these. The only easy method will be the front 3 into the new headpipe, & 5 into the stocker, blocking between them. It's a sound unlike anything else - one pipe raps an instant after the other ... if your car has an underseat heater, you're in for some clever exhaust routing.
thnx for the feedback . just spent the day taking out front three freeze plugs.pretty bad ,but I doubt it iwas more than a contribution . seems as though the front half o[is getting hotter than the rear . temp sender is in the rear.and the gauge is slow to come up , so I think circulation is blocked . felt like the lower rad. hose was much cooler than the top as well . I'm not familiar with the tube spoke of . is it checkable replaceable . ive flushed the block pretty good with the 3 front freeze plugs out . running pretty clear . I'm thinking maybe having the rad. rodded might be a good next move. also theres a outlet on the bottom of the rad. for the heater , but no inlet .there is what looks like a plugged inlet on the head . is that where it returns , that 48 is soooo bad as ! bet ya wish youd!!! thnx again for input . my father inlaw , now gone , said he heard a buick strat 8 split , and it was the best ever
You might wants to make sure the bottom radiator hose isn't collapsing under acceleration. Feel around the face of the radiator ( finned area ) for cold spots to see if radiator is plugged.
Brown and tan, eh? Reminds me of an early 80s corvette pace car. Those are beautiful cars but man! You GOTTA change the paint color! A guy here use to have a 50 in gloss black, lowered with a set of nice aluminum wheels on it. It was beautiful.
what a great looking car I would own one of those in a heartbeat , here in aus we only had fourdoor sedans , I had a six cyl sedan it was a great car
That's a very common failure with those. They don't cool well, that's the hot spot in the block. The OP doesn't say how hot "hot" is, but if it's overheating AT ALL, don't drive it until you know what's going on and fix the problem.
I'm all in for hating the paint . my wife likes it . sure glad her vote doesnt count . black is what I'm thinking ,as well . and I have a new $400.oo spraygun. first ive heard about the common heating problem . sure hope I can get a handle on it . really like the 8 . way to easy to put in a sbc , but I think that's already been done . 25 yrs ago when I got my 50 wayfarer , all I could think about on the way home was sbc/turbo etc etc . sure glad I never did it!! NOTHING sounds like my 230 flatty with twice pipes , AND with 300 rear gears 20 mpg at 70 mph . would like more info on the cooling tube?????
you people down under may not have had torpedoes , but you have utes . fair trade!!! did Pontiac make any utes?? I liked them so much , I made my own . out of a pinto wagon . grt car . and would and did carry 2000lbs.
Hi Bill, the tube sits directly behind the water pump in the coolant channel between the cylinders and the valve seats, the pump is pressing the water into it, the holes in the tube are showing towards the valve seats to serve them a good cooling. just found one on ebay: https://www.ebay.com/itm/1937-1954-...274265?hash=item283f096d59:g:dCMAAOSwK31Zsb-U when i pulled out mine, the rear 3 inches were rottened away, so the last cylinders could get some heat trouble. when i wanted a new tube, it wasn't in stock at the known dealers, later i found one on ebay. i usually buy lots of stuff at California Pontiac Restoration, it is in there catalogue, but was not available the last time. Cheers, Carsten
thnx for the info . isit hard to remove /replace . I'm pulling my rad. today to have it rodded . I assume once its out of the way ,and the pump should be a no brainer .did you replace yours in a running mtr , or part of a rebuild . did it run cool after . thnx
i replaced mine in a running motor, after that i never had any temperature trouble, but before also not, the gauge always showed o.k. but there's only the one sending unit up in the cylinder head, it doesn't tell anything about the real temperatures in the engine. after the pump was out, it was easy to pull out of the engine block.
i have a cheap simple infrared thermometer, it's quite interesting to watch several spots on the hot engine. i can't say anything bad about the straight eight, running smooth, strong and reliable. and i made me a stainless dual exhaust, she purrs like a kitten.
did you split it 3/5? could someone easily make the dist tube . 100 bucks for new . looks like exhaust tubing might do . stainless??
You could make the tube of brass or stainless. It is like a round tube flattened into an oval. It might be tricky to get the exact size and shape, it has to fit into a restricted space and the holes have to be the right size and position. Before you do that check the temperature of the head from front to back. If it is the same all the way along the old tube is good. I don't know about Pontiac but some Chrysler products used a brass tube that is good for the life of the car. Others used galvanized steel which can rust away. I pulled mine out of a Chrysler six and cleaned it but would not do so again unless I had to. It was in there pretty tight and I damaged it in pulling it out but was able to repair it. It took a couple of days to persuade it out without wrecking it completely.
no, i splitted just the exhaust pipe after the last go-thru in the frame. the header is still stock. the silencer flew out shortly after, it was just to quiet.
no Pontiac utes , only chevy however bill get me a torpedo and you will have a ute no probs 2 of my friends have running driving 49/50 chev utes no one wants the ugly heaps
list’n to the wife! That color scheme could be rad! Everyone has a black car Sent from my iPhone using The H.A.M.B. mobile app
Man, love that color scheme on that Chevy above...my bro had a '47 with similar paint... But his was a Ford Chamois tan and a Ford red (can't remember the name of it tho). Please don't paint the car black...!!! Anyway, a friend had a Buick straight eight in his '39 and put headers on it...it sounded just like a V8. FWIW, I'm also working on a fastback-a '48 Caddy...put a '68 Nova sub-frame in it so far...will be adding a nine inch Ford rear end... Good luck with your fastback, they make great looking sleds... R-
thnx , red your post top to bottom . very inspirational ! love what your doing . I'm really hoping to keep my strt 8 /hydro the rad. is in the shop being rodded out now . should be done today. pulled the first 3 freeze plugs and back flushed dug etc. etc.. my rad. man has some commercial block soap he gave me . WAY better than anything from pep boys . works so good , it will plug up rad. heater core etc . did it seem like you had access to the tube mentioned above? I'm going to install the rad. , and see if I need to go further .the mtr. runs so smooth I think it is in good condition .according to the stock gauge ,the oil pressure is lower than I would like , but if need be I will remove/replace the bearings . would sure rather not though . the way they were built isn't that simple to work on. still not sure where the heater return line goes
I had limited access to my water distribution tube. I could slide it partway out, but not completely. If I pulled the grille, I could have removed it. Not sure if yours would be harder or easier to remove in the older body. My water tube was brass; I think all the Pontiacs had brass water tubes. Much more resistant to corrosion than the steel tubes used by some other makes. If you find that yours is corroded, you should be able to get a replacement from California Pontiac Restorations.
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