FYI FORD MustangSteve's Ford Mustang Forum / 1965 Ford 289 valve adjustment and idling issue

**Posted by moon4964** 12/20/2024 3:37 PM

Good afternoon, gentlemen.
My 289 is acting up. I recently got my car roadworthy and discovered that wires 2 & 3 were crossed at the distributor cap. The rough idle and missing were cured. However, the rocker arms were clacking, so I adjusted the valves properly this time. They had only been adjusted statically when the engine had been assembled the 8 years ago. This time I also adjusted them statically and in the proper firing order (1-5-4-2-6-3-7-8).
BTW, I drove the car with the misadjusted valves for 30+ miles over a four-day period. It ran okay despite the clacking.
The problem is this: The clacking is gone, but the engine will only run when I keep the revs up (above 2500 RPM, constantly feathering the pedal). As soon as I let up on the gas the engine slows down and dies. It can be started immediately but dies again when the pedal is released. The engine revs like a champ and does sound strong, but it will not idle. I detected a slight miss at the high revs, but I am not sure if this is part of the problem. There was no miss before I readjusted the valves.
I will be able to get back on it after the New Year, but I will appreciate any ideas. The car is a 1964 Falcon, 289, 4 spd with the Mustang Steve clutch cable kit. Merry Christmas.

**Posted by Greg B** 12/20/2024 5:32 PM

Nice! I had one back in Hs. I also had a two door post and a 67 two door post.

As for your engine, lots of questions to digest before one could really help. Stock cam?

Did the lifters bleed down properly before you re adjusted them?

I suggest watching a you tube video or two on re adjusting rockers on an already run engine. Then things can be eliminated one by one like say the carb accelerator pump diaphram, which are notorious for hardening with today's fuels. Timing. Plugs. Etc. Etc.

**Posted by moon4964** 12/20/2024 6:54 PM

Stock cam, hyd lifters. EdelbrIock 500 CFM carb. I have watched a couple videos and followed their instructions. I will watch them again. Can you explain the 'bleed down' comment? What puzzled me is that the engine ran rather well when things were not adjusted properly. Just the clacking of the rocker arms. I will be looking at the carb more closely when I get back after the New Year.

**Posted by Greg B** 12/20/2024 7:12 PM

https://www.onallcylinders.com/2016/10/20/ask-away-jeff-smith-set-preload-hydraulic-lifters-important/

On a new lifter, that little center piston pushes real easy. After an engine has been run, if the lifter is functioning properly, those lifters fill up with oil, and can be very hard to press back down, hence bleed. So on an engine that was improperly adjusted from the build, they can be full of oil and stubborn. This is what the article starts to talk about further down. The idea is to get to zero lash, with that inner piston not compressed, THEN the final turn is what slightly compresses the inner piston of the lifter. Problems arise when one is bottomed out, or refuses to bleed down.

**Posted by moon4964** 12/20/2024 7:28 PM

Thanks, Greg B.I have read the explanations and will try to digest them.

**Posted by MS** 12/20/2024 11:07 PM

Since it ran fine with valves a bit loose and runs bad after adjustment, I am betting you overtightened the adjustment. The valves are now held open slightly causing it to lose compression and not run.
You need to adjust the valves properly.

**Posted by moon4964** 12/20/2024 11:35 PM

Thanks, Steve. I will make the adjustments after the New Year and report back.

**Posted by RTM** 12/21/2024 7:21 AM

I agree with MS, most likely to tight.

**Posted by TKOPerformance** 12/21/2024 7:42 AM

Yep, I concur. I did this on a 350 I built years ago. My neighbor came over and head it crank and knew immediately what I did wrong. He adjusted the valves and she lit off immediately.

**Posted by Nos681** 12/21/2024 8:44 AM

This video will help ya.
I do it slightly different than described in video.
I move pushrod up and down until play is gone.
Then I add the additional 1/2-3/4 turn past “Zero Lash”

https://youtu.be/5EGlb_VpTAw?si=8ymIjS4Mr4gtwT-B

Last edited by Nos681 (12/21/2024 9:03 AM)

**Posted by MS** 12/21/2024 9:34 AM

After loosening the rocker, rotate the pushrod between your fingers while tightening the rocker until you just feel the pushrod stop turning. Then rotate an additional 1/2 turn. Then go to the next valve, always following the order as described in the picture.

I have thet picture in my shop because I can never remember which one to do.

**Posted by moon4964** 12/21/2024 12:31 PM

AS I stated, I will be going through the procedure after the New Year. I have been adjusting them statically. Is this the recommended procedure? This was the method i used when I built the engine.

**Posted by TKOPerformance** 12/21/2024 12:53 PM

I've never been a fan of adjusting them while the engine is running. It tends to throw oil everywhere. I've seen guys cut up old valve covers to try and make shields to lessen it, but its still an unnecessary mess IMO. No reason not to do them statically, especially on a hydraulic cam.

Personally I've never had much luck trying to turn the pushrods. They always come out too tight when I do it that way. I move the pushrod up an down instead. when the slack is gone I go another 1/2 turn

**Posted by MS** 12/21/2024 4:10 PM

TKO, you just aren’t holding your mouth right…

**Posted by John Ha** 12/21/2024 4:44 PM

If it ran properly before adjusting and crappy after, it's possible that you jarred something loose or reconnected something incorrectly after the job was done. Take a close look, at everything, to make sure everything's where it should be. Always check the easy things first.

**Posted by Ron68** 12/21/2024 4:55 PM

John Ha wrote:
If it ran properly before adjusting and crappy after, it's possible that you jarred something loose or reconnected something incorrectly after the job was done. Take a close look, at everything, to make sure everything's where it should be. Always check the easy things first.

Yup - if it ran good, and you did something to it, and it runs crappy - go back to the last thing you did and check that. Also, make single adjustments and ops check them before moving on to another step. Making multiple adjustments at once makes it harder to pinpoint which adjustment you made is causing the problem, if it still runs bad.

**Posted by moon4964** 12/21/2024 5:20 PM

All will be revealed, gentlemen, after the New Year. Each of you has been very helpful.

**Posted by 6sally6** 12/22/2024 4:45 PM

I'll be the last to say it.... adjust the valves like stated above. BECAUSE.......
Back when I was "less-learned".. I decided to adjust the valves (while running) to quieten down the old 302 engine in a truck I just bought. I went through it a couple times to make the 'click-clack' go away. (it did)
I didn't drive it very long at all before it started skipping.
Burnt an exhaust valve !
Expensive life lesson
6sally6

Last edited by 6sally6 (12/22/2024 4:46 PM)