still having a few problems with engine getting hot in city at stop lights.. I finally got the fan inside the shroud which has helped more. but I am looking for a better shroud that covers better. mine goes all the way around but has lots of open spots. on the sides. where it butts up against radiator. and around top rad. hose. I have seen bigger better shrouds on some 70 formula 400's but did'nt get a chance to talk to owner. I have 68 with new 3 core rad. with new clutch fan.. and new plates in pump. was also told that if you powder coat plates in pump that help alot..
1) how "hot" is hot? 2) shroud should not cover the fan....fan should be 50/50 in /out of the shroud 'bigger,better' shrouds?? you should use the "original" style shroud
Both responses above are dead on, one clarification, 19.5" 7-blade clutch fan 50/50 inside a stock shroud, all upper fillers, lower filler/baffle, rubber fillers on both sides in front of radiator, 180* stock thermostat, proper water pump AND pulleys, correct timing, carb setup etc. This topic pops up almost weekly and if you do the research, anyone who has done ALL of the above, has solved this "hot" issue.
It all goes back to basics and installing ALL of the correct/OEM components that made up a perfectly working cooling system back in the day.
I had an opportunity to speak with an older gentleman who was a lifelong Pontiac mechanic back in the hay day. I specifically asked him about these cars and if they ran hot out of the box when new.
He simply said NO! In fact, he said that these "hot" issues didn't come about until people started playing with these cars. Things such as headers, switching carbs, cams, rads, intakes and the list goes on. He said every old Pontiac that came in the shop with running hot issues, was ALWAYS modified in some way.
I can only speak from my own personal experience on this topic. Once I had rebuilt my 68 Bird 400/4-speed pushing 405hp at the rear wheels, back to OEM specs with ALL of the above mentioned parts and pieces, I went from 7 YEARS of running hot to NEVER running hot in the matter of one day. The very day I completed installing all the OEM/stock/original parts and pieces. The last piece of the puzzle for me was the 19.5" 7-blade clutch fan.
The day I installed that fan (every other OEM part was in place) ALL of my hot issues were gone forever! After that, I would drive the Bird on Daytona Beach in 98* temps at 5mph for a 7-10 mile stretch on the beach and NEVER once ran over 190* and NEVER ONCE boiled over and never having a recovery bottle as well. This was a car that for 7 years could NOT sit through a redlight for two cycles without overheating!
Going back to the basics will solve hot issues on these old Pontiacs. However, you must find and install ALL of these parts as they rely on one another to make a fully functional cooling system...
Good point. I've had seven Pontiacs from a 49 Torpedo-Back to a stock 69 GTO and never had an overheating problem, my 68 bird has had issues but it's modified.
thank you very much for the feed back,, the mods I have are, i had emailed edlebrock and wanted a little upgrade and they sent me specs for little bigger cam, matching carb, (1406)(i believe) and timing chain and gear. also have headers. Where is a good place to get all upper fillers, lower filler/baffle, rubber fillers on both sides in front of radiator. I do need to mess with the timing a little, and am running stock dist.
The upper "400" fillers aka: X-fillers are available in fiberglass and or metal as per OEM. The metal ones are better. Lower baffle available in fiberglass only, better off looking for a steel OEM part, masticated rubber raditor to rad support fillers are available from most parts places...
