Hot Rod Forum banner

1969 Ford 390 ticking @ 1200 RPM

7K views 11 replies 3 participants last post by  69 widetrack 
#1 ·
I have a 66' F100, 390 FE. The engine develops a "ticking" sound above 1200 rpm, it is not an exhaust leak, and I have replaced the four lifters on the passenger side rear two cylinders where the noise was initially thought to be coming from. I have replaced the broken rocker shaft spacer springs with the aluminium DSC spacer & washer kit. I am getting plenty of oil to the rocker shafts and as stated the ticking noise that sounds like a stuck lifter appears at and above 1200 RPM. The old truck runs great and has plenty of power, could the problem be worn out rocker arms?
 
#2 ·
It could be many things, rockers are a possibility, but why, when you had the engine apart didn't you replace all the lifters...It's open and lifters don't cost that much...very often the noise can transfer through metal and what you think your hearing at one place can be coming from a totally different place. The only way you can eliminate lifters as the culprit is to replace all of them.

You say that it's not an exhaust leak, could it be a heat riser valve? I'm trying to remember but I'm sure that you have one. It is possible that the shaft holding the butterfly valve in place has worn out and at a certain RPM you have enough exhaust flow to cause the ticking noise without it leaking.

Best to you
Ray
 
#3 ·
69' Ford 390 ticking noise @ 1200 rpm

We initially pulled the engine to replace a leaking rear main seal. while the engine was on the stand we pulled the pan and replaced the front crank seal as well. The 66' F100 sat for awhile, so I changed the oil and added a quart of SeaFoam and ran the truck to clean up the engine. The noise was present prior to removing the engine. We removed and inspected the rod & main bearings, they were like new. The cross-hatch was still clearly visible on all eight cylinders. This engiine was purchased with an aftermarket aluminium intake & carb (Edelbrock) and we did not remove the intake. We were able to get the lifters on the two right rear cylinder out with out removing the intake manifold. We have only run the engine thru several cycles of running it up to operating temperature, it has not yet been out on an extended drive. The ticking does not get louder at higher rpm, but is noticeable, like a lifter sticking, the engine had some crud in it like an engine that was not run up to temperature, the SeaFoam took a lot of it out.:)
 
#4 ·
I'm sorry if I sound a little direct...and I don't mean to sound rude, but, if you suspected lifters, the engine is out of the truck, you replaced, both front and rear main seals, why would you not take off the intake and replace all the lifters when the engine was on the stand and eliminate lifters all together? What you'v done is eliminate 25% of a potential problem, doctors rarely operate on humans with those odds. If it is the lifters and they are just sticking, they may free up with the additive that you put in it and hopefully they will...What did the bottom of the lifters that you replaced look like, where they dished on the bottom or flat?

It's good to hear that the bearings looked good, I assume you looked at the cross hatch on the cylinders from the bottom, because if you never had the intake off, then the heads never came off and most of the cross hatch you saw was where the piston didn't spend most of it's crucial wear time. So again, not to be rude, but looking at cross hatches from the bottom, only tells you that the engine has been cross hatched recently, it doesn't tell you what's happening up top and that's where all the action happens.

It may be something as simple as the heat riser valve, is the tick constant at 1,200 RPM or does the noise lighten up a little under load and come back when the RPM drops? It's hard to give a diagnosis when I can't hear the engine...but look at the bottom of the lifters and check for ware...that's a start and see if the heat riser valve has play in the shaft.

Ray
 
#5 ·
Ray, no offense taken. The reason that I posted this is to get input from good folks like yourself. The lifters looked great, they were not dished or scuffed in any way. Where is this heat riser valve located? I might have forgotten to mention that this truck is equipped with a set of headers. We made darn sure that they are not leaking, we installed a set of Percy's header gaskets to be sure. I think that if the noise doesn't cease after driving the old truck, we will pull the intake and change ALL of the lifters, the lifters that we installed were Melling from O'Reilly Auto Parts. I was given all of the receipts from the rebuild of the 390 from the previous owner for each and every part as well as the machine work performed, the engine has 4,500 miles on it since it was rebuilt, but it sat in a garage for 2 1/2 years prior to me purchasing it. :)
 
#6 ·
Thank you for understanding, to me (and maybe to me only) if I suspect a problem that has 16 potentials, I replace all 16 when I have the opportunity, just for insurance and elimination purposes...headers, no heat riser valve...one potential eliminated.

Lifters have a distinct sound, it's almost like a hollow tick...try your running the engine for a while, after sitting that long I'd' be a little sticky too. I'm not familiar with sea foam as an additive...for sticky lifters in the sixties cars I always used Wynn's Engine Tune Up oil additive...even when my lifters where worn out, it quieted them down for a while...if yours aren't worn out it might free them up, and, if it does quiet them down for a while, you know it's lifters.

Hope it works
Ray
 
#7 ·
I will try running CD-2 in my 390 and see what happens. If the noise persists, I will replace all 16 lifters as well as the camshaft. I appreciate the time that you have taken to answer my posts. I hope that you and your have a very Merry Christmas and a happy and prosperous New Year!!:)
 
#8 ·
I thank you very much for your well wishes and I wish the same for you and yours. I also wish that the suggestions solve your problems, there are many things that can cause that type of noise in an engine and the trick is to eliminate the common things that can cause the noise.. It may be wise to take a look at the rockers again, usually if they make noise they make it at all RPM's, but it doesn't take much to have a look for wear. Let me know how it turns out, and again, I wish you the best.

Ray
 
This post has been deleted
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top