I fired up my 350 in my '57 panel today for the first time. I've had the engine for 3 years, and time and life delayed me until now.
Upon firing it up today, it ran great, but I noticed smoking from the passenger side. I ran over to check, and the new paint on my new headers was BUBBLING. I quickly shut it down, but it sounded like it was running fine. The area most impacted were the exhaust headers for cylinders 2,4, and 6.
I did not have a temp gauge on the engine, as this was my first time firing it up, and no sending units are connected to anything. Any ideas on what could be driving the high heat? Was it just bc it was new paint taking a hit? Timing issue? Other?
Like I said, the engine ran solid, but I didn't want to let it keep going until something bad happened.
Headers and paint- - - - -that's a lost cause! Powder coating, maybe, but I've never seen any kind of paint, including the "high temperature header paint" that will last more than a few minutes, or the first hard uphill pull, whichever comes first. The temperature sensors on our dyno headers would indicate exhaust port temps of 2,000 degrees or so on a full-throttle run under load. No paint in the world is going to survive temps like that.
Late ignition timing and/or a lean mixture will cause cast iron exhaust manifolds to run red hot. Headers will get hot enough to melt spark plug wires and blow out gaskets. After over 50 years of building race engines, somebody would have to chase me a long way to try to GIVE me a set of headers! Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.
Thanks all for your replies- I knew the paint would burn off *eventually*, but not on fire 1!!
I had a pair of painted Hooker Headers on a 327, and they did not react like this in the beginning at all! These are Hedman headers, so, maybe they heat up quicker? I don't know, it was just really weird.
Hy pan3lman, are your headers connected to a full exhaust system, or are there just headers on the engine? If it has been sitting for a while could rodents have moved into the exhaust pipes and their nest be causing a restriction?
Hy pan3lman, are your headers connected to a full exhaust system, or are there just headers on the engine? If it has been sitting for a while could rodents have moved into the exhaust pipes and their nest be causing a restriction?
Thanks for your thoughts! The engine was sitting in my garage for 3 years with no exhaust headers on it. Once I reinstalled it in the truck about a month ago, I was sure to put plastic bags in the exhaust ports to mitigate the chances of anything getting into it while outside. I installed the headers about a week after that max, and all of that was only about 2-3 weeks ago. I don't know if there's any chance that anything could have been living inside the cylinders prior to the engine and header install, but I'm thinking that me firing it up yesterday would have changed that really quick!
Flame sprayed aluminum is a header coating that gives a unique appearance, is permanent, will not discolor and prevents rust. I first saw it as a coating on air cooled radial aircraft engines and thought "That would look really cool on headers". So I took a set of headers I had just built to the aircraft engine shop where I saw the process applied to cylinders and had the headers coated. The result was perfect in every way.
That was decades ago and apparently aluminum flame spraying is still offered:
I last had flame spraying done about 15 years ago on this roadster exhaust, and the coating is unchanged from the day it was applied. For a shiny surface the flame sprayed aluminum coating can be buffed and looks like any other polished aluminum.
Paint on headers, for a couple of minutes, lol. Usually does better then a couple of minutes if you used the hi temp stuff. If plasti cost, probably not. Could also be running lean at idle And higher temp for that reason. High temp powder paint works for a little while, but eventually fails. I have it on my headers and it started to fail after year two.
Paint on headers, for a couple of minutes, lol. Usually does better then a couple of minutes if you used the hi temp stuff. If plasti cost, probably not. Could also be running lean at idle And higher temp for that reason. High temp powder paint works for a little while, but eventually fails. I have it on my headers and it started to fail after year two.
I agree, and yep it was Rustoleum high temp. If I have time today, I'm going to throw my timing light on it to see if it's too retarded.
