1979 403 Lifter Tap?

[maddog5150]

Greetings board,

I have a 1979 Special Edition 403. It sounds like it has a lifter tap on the left side of the engine.

A few months back I was surfing some T/A website and it had the Top 10 ways to know a mechanic is not a Pontiac specialist. One of the ways was theat they misdiagnose the noise as a lifter tap but is really something else on the 403 engine. Anybody have an idea what it is or do you remember the website that mentieond this?

I seem to remember something about the rockers, but I'm not 100% sure.

Also, can anyone recommend a good mechanic and body shop in NJ, lower NY State or CT that specializes in F-bodies (especially Trans Ams) and really knows what they are doing? I know about Texas Trans Ams but I don't really want to take the car all the way to TX.

Advice please?

Thanks!

Pete in NJ

[maddog5150]

Greetings board,

I have a 1979 Special Edition 403. It sounds like it has a lifter tap on the left side of the engine.

A few months back I was surfing some T/A website and it had the Top 10 ways to know a mechanic is not a Pontiac specialist. One of the ways was theat they misdiagnose the noise as a lifter tap but is really something else on the 403 engine. Anybody have an idea what it is or do you remember the website that mentieond this?

I seem to remember something about the rockers, but I'm not 100% sure.

Also, can anyone recommend a good mechanic and body shop in NJ, lower NY State or CT that specializes in F-bodies (especially Trans Ams) and really knows what they are doing? I know about Texas Trans Ams but I don't really want to take the car all the way to TX.

Advice please?

Thanks!

Pete in NJ

[mike nixon]

the rocker bridegs are probably worn on that cyl.

they're realitivly cheap and i'd put them all on that side when i had it apart.

when it's down be sure the pushrod is moving a good supply of oil to the roacker asm.

if you want to haul it to ind, i'll fix it for you. http://forums.performanceyears.com/groupee_common/emoticons/icon_wink.gif



mike

[Brian Baker]

The rocker arms are held in place with pedestal looking "bridges" (like Mike said). They can wear, causing the tick. I've also experienced broken valvesprings in the 403 when it was run low on oil (not enough oil to top end, springs got hot and failed). Is it running rough?

[maddog5150]

Thanks guys.

Yes it is running but that ticking tap noise is driving me crazy. And by the way, it does not go away when the car warms up.

Pete

[olblue]

Sound like my old 1965 always did. I'll bet you have oil pressure issues as well.

[maddog5150]

My oil pressure runs around 50 psi when the car is cold but drops to about 25 when it gets warmed up. Is that too low?

[Jaggs79transam]

My 79 ran about the same oil pressure before I lost the motor to a main cap problem.

60 on new fresh oil at startup and 30 when warm.

We thought my valves were ticking but could not find any problems with the motor. (with a very experienced mechanic) and it ran real strong! Well about a month later it was like 2 hammers being hit together.

Turns out my carb was dumping gas into the oil and I lost #2,3,7,8 crank bearings was not a good day. He didn't find gas in the oil because I had just changed it and had not run the car enough to pump more gas into the oil yet.

Well thats my story and I would let Mike Nixon fix it if he is familiar with the motor (not many 403 mech's around anymore)