Lifter replacement questions

[Ronin8002]

I've been working on getting my engine (130k miles...God bless it ) prepped for a BBK S/C install sometime later this year. For about a year or so now, I've been hearing sounds in my engine that from what I understand is the infamous "lifter noise," (i.e.....some clattering on a cold start which goes away after the engine has warmed up). Using Gunk motor flush, Lucas oil stabilizer, and Purolator filters hasn't fixed the noise.....I'm not using/leaking oil either. So...I'm looking at replacing rocker arms, pushrods, and (maybe) lifters.

Questions:

When I do take off my valve covers to inspect my rocker arms and pushrods....am I correct in assuming that gaps between the rockers and valves = bad lifters? If I don't see any gaps....does it seem reasonable to assume that my lifters are still good (meaning that I just put in rocker arms and pushrods)? Or should I go ahead and replace the lifters as well to prevent any future problems?

Since Vanir seems to be out of the business of selling these parts on their site...suggestions on good places to get the parts?

Also...my Haynes manual states that the cam should be replaced when the lifters are replaced....is this necessary?

Thanks to all on this board who have helped me with other things before...advice on this matter would also be greatly appreciated.


-James

 

[Ronin8002]

Oh, also....the suspected lifter noise I'm hearing doesn't happen while at idle or while revving it in P or N....only when I've made a cold start and have put it in gear and have begun driving.

 

[Rhett]

I can't answer all of your questions. However, I will say this; If the cam does need to be replaced, I would replace it with a cam similar to the one SteveVB has put in his navajo, rather than a stock cam. Then later you could get a chip custom programmed for the supercharger and the cam. The stock cam on the OHV is ok, but it's optimized for torque; so what I'm saying is you might look into a different cam. I know Vanir used to offer cams for the 4.0; I am not sure where else to get them but I know SteveVB here has one. I'm not sure where he got his.

 

[Raceit]

On your gap question....here is a pic of a rocker arm that is not touching the top of the valve stem. Hence all the noise.
(It's the one with the red markings on the spring)

Here's the acompianing write up I did a while ago...
http://www.explorer4x4.com/lifters/lifters.htm

Also with the gap it will depend on where your engine happened to stop to either compress or release any lifters. So if you don't find any gaps you might have to crank the engine by hand to find them.


On the cam being replaced...It will depend on how much wear it has. My engine had about 168K miles on it when my lifters were replaced. And when you tear in to it I was able to check the cam. I was able to stick my finger down there and it seemed smooth as glass. Plus visually it seemed fine. No grooves and the rollers on the lifters also seemed fine. So I left the cam in.


I got all my parts from Stevens Parts in Fort Worth, TX.
http://www.stevensparts.com/
They seemed to be pretty familiar with our 4.0L valve clatter problems. They had some good deals at my time of purchase with their "take-off" parts. They were new, they just couldn't be labeled as such.

 

[SteveVB]

I got my CompCams 410 cam from Summit Racing - they can order one for you- Another source is CamCraft.com, they can grind you a custom "blower" cam. Comp cams has 2 avail- the 410 and 422 check thier site for details, they have a catalog online.

I think the "replace the cam with lifters"statement is a stock statement they put in the repair manuals, and deals mostly with flat tappet cams which MUST have the lifters and cam replaced together since the lifter wears specific to the cam. The cam in the 4.0 is a steel roller cam and since its a roller the cam and lifters dont wear the same as a flat tappet. So you can reuse the lifters on a new cam, or replace the lifters with no problems. As long as a roller gets lube it should be OK.

Steves write up is a must if you are going to tear into the heads.

I got most of my take offs from Vanir, but Sven is out of the 4.0 business. Stevens is a place to get parts, also Fordpartsnetwork. I would also look to Dead Link Removed they sell rockers with wear cups installed.

One of the problems with the 4.0 is that the rockers seem to wear in the cup and at the tip. Check them all very carefully, although it will be readily seen that the pushrods have worn into the rockers and the valve stems have eroded the tips. So a replacement rocker assembly at rebuild is a must in my book. Some flame hardening of the tips and cups has been suggested - I found out AFTER I did all my work, but it would make sense judging by the rockers Ive personally seen. And you can get replacement pushrods of any length (if you install an aftermarket cam you need custom length push rods) from Smith Bros - www.pushrods.net. They supplied Svens (vanir)pushrods as far as I know. New hollow tube pushrods will save a bit of weight and will allow the rpms to come up a bit quicker- may not be noticable, but less weight to move in the valvetrain is a good thing.

If you are prepping for a blower a cam change would be a good idea, also new valve springs (with a new cam or not) would be a good idea since you have 130k on the engine.

If you have taken halfway decent care of the engine, a top end rebuild is likely to be all it will need. When I had my 140-50k mle engine apart the bottom end wear was non existant- the top end was trash though. Good Luck.

Almost forgot- look up Doug904 he posts on thsi site every so often- he will have some sources and sells 4.0 parts.