Results of poor valve adjustment of 409 425 hp motor?
- Thread starter Michael Cohen
- Start date
I don't know about "had a number of stock 2x4 intakes in their possession"? (Aubrey's post of Dec 21) What I know now is that wrong diameter and probably wrong length of pushrods were used. I also parsed from my builder that he did not use an adjustable push rods to measure each intake and exhaust push rod length. He used the same length as was used on the prior build from Michigan. I have to find out if during the rebuild in Ca. if any amount of metal was shaved off the heads. I have purchased from summit racing two adjustable rods. They come in a set. I read on a prior forum area the procedure to measure the length. One question I read was you must measure with a solid lifter in place and then replace with a hydraulic lifter when installing the new push rods. Question is are all 409 425 hp solid lifters the same dimension? stock ? Can I buy just one or two for measurement purposes? Can't find the post again. Tried the same search as before but did not find the procedure. Help?
Since I know now things are not right my inclination is not to use the engine for fear of more possible damage? Want to remove too narrow push rods. And replace what look like BBC big block springs.Has anyone known of a builder using the wrong diameter push rods and had the motor survive? What are the best springs to use in 409 425 hp motor?
Since I know now things are not right my inclination is not to use the engine for fear of more possible damage? Want to remove too narrow push rods. And replace what look like BBC big block springs.Has anyone known of a builder using the wrong diameter push rods and had the motor survive? What are the best springs to use in 409 425 hp motor?
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I DONT want to seem like I'm trying to make more work here,but the spring you'll need will depend on the kind [lift,duration,ramp speed] of cam you're trying to use.Hopefully there's a build sheet in your paper work that can answer that question.IF I remember the start of this post correctly,you were trying to get the valves adjusted using solid ,if so,use the solid lifters in the engine now for pushrod measurement.IF it turns out that your cam is a hydraullic grind,you'll still be ok.As Phil mentioned,examine the push rod holes for wear or damage.
Pull the motor and bring it to somebody who knows these motors. If you keep f-ing around, it is going to cost even more. Hate to sound dense, but this will go from bad to worse in a heartbeat. I am sorry to hear you are having problems, and we are trying to aim you in the right direction, but you need somebody skilled to inspect your motor and make suggestions based on what is seen, not conveyed in a discussion.
MRHP has it right.
I believe I read somewhere on this post that this engine is the original for your car. Don't get in a hurry and ruin your engine. It is irreplaceable................There is one thing that you want to always remember-----------THERE'S NEVER TIME TO DO IT RIGHT, BUT THERE'S ALWAYS TIME TO DO IT OVER.........................
It appears that you don't have money to burn. Don't start a fire with it. Listen to these guys.
It appears that you don't have money to burn. Don't start a fire with it. Listen to these guys.
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Post #73
Some further info. Not only were the pushrods the wrong size but they were made for Ford engines! Put proper size 409 pushrods and put lock nuts on the rockers now running dependably. Still must use a high amount of 100 octane with 91. About 5 gallons of 100 to about 10 gallons of 91 to prevent pinging. Anyone ran an oil cooler with their 409?
Also went to the beehive style springs.
Car has been running cool and strong with Crane Gold rockers and the right push rods. Very powerful motor. Still have not had the space or time to open it up cause of where I live. Few open spaces and many police in the area. But one of my cars is an IS F and the 63 409 seems to pull twice as strong as the F.
After many hrs of change and experimentation motor runs great and cool and seems to be fine. All is well in 409 land tonight! Oh sorry guys back east with the weather but today 72 degrees and sunny in LA. But traffic is bad! Heh Heh Heh
Slow down[it's winter anyway] now so you can speed up confidently later...............PLEASE!
Winter? WTF, this is Southern Calif my friend we don't have no stinken winter.