4.6 cam in 4.0 engine
- Thread starter RWF
- Start date
The thing I do not like about D&D's cam is he does not cut them to accept the thrust washer. The thrust washer keeps the cam from walking at idle. D&D's cams are notorious for walking and making a knocking sound at low RPMs.
As for pushrods, I've never heard of people reusing them. Never. I did a search to see what others were saying, and I still cannot find a reputable site suggesting it's okay to reuse old pushrods. But it sounds like you have not even pulled the old ones, yet. When you do, roll them on a flat surface and tell us how many are tweaked.
As for pushrods, I've never heard of people reusing them. Never. I did a search to see what others were saying, and I still cannot find a reputable site suggesting it's okay to reuse old pushrods. But it sounds like you have not even pulled the old ones, yet. When you do, roll them on a flat surface and tell us how many are tweaked.
They will be out soon and I promise to report on the pushrod condition assuming I don't hit myself in the head w/the BFH, and if my memory will kick in at the appropriate time in the future. But I can't imagine they will be in like new condition. I consulted my trusty 8 ball on this cam, lifter & pushrod question and the response was about as mixed as the posts here but not nearly as interesting, what a surprise. Now what was I tryin' to remember?
My 120K mile pushrods are straight according to my granite table.
Am I a hack?
Can anyone provide the length and tolerances of the stock pushrod so we all are able to know if our used pushrods are acceptable? I assume someone must know this so that we can establish if we are hacks or not.
All I do know is that I have sufficient pre-load on my lifters that I can assume whatever length the pushrods are meant to be is acceptable for my engine. But am I still a hack?
Am I a hack?
Can anyone provide the length and tolerances of the stock pushrod so we all are able to know if our used pushrods are acceptable? I assume someone must know this so that we can establish if we are hacks or not.
All I do know is that I have sufficient pre-load on my lifters that I can assume whatever length the pushrods are meant to be is acceptable for my engine. But am I still a hack?
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Id be the last to agree with dan but I do agree pushrods are worth changin. The lifters are hydrolic so they self adjust and with new lifters it eliminates wear patterns. And theyre cheap so why not.
ptschram
Well-known member
D Chapman said:
HYDRAULIC TAPPETS RENEW
Service repair no - 12.29.57
1. Remove rocker shafts. See Rocker Shaft
Renew
2. Remove intake manifold. See FUEL SYSTEM,
Repair, Intake Manifold
3. Remove push rods, retain in removal sequence.
4. Remove hydraulic tappets
5. Fit tappets, push rods and rocker assemblies.
See V8i Overhaul Manual.
6. Fit inlet manifold.
7. Reverse removal procedure
You are an ignorant hack Chapman. The large journal blocks do not even have provision for the retaining plate and none of the three or four trucks I have in the driveway right now with Crower cams bought from Mark have problems with knocking from the cam.
The only time I've seen a pushrod bend was when there was interference between a piston and a valve. If it was even remotely wise to replace absent damage, I'm certain that Land Rover would have made some reference in the FSM.
I suspect that sites suggesting replacement also sell those same parts. I regularly discourage folks from spending money they don't need to so I guess I'm not a reputable "site" as I don't encourage such spendthrift behavior.
i agree with pt. new rods are a waste of $100, but peace of mind is priceless right? the only time i've seen bent rods is when the timing chain has slipped and that was only on early rigs with the fiber gears.
ptschram
Well-known member
robertf said:
3.5,3.9, 4.2 blocks have smaller main journals than the 4.0/4.6 and the blocks do not have provisions for the camshaft retaining plate.
Oops, the smaller journal blocks don't have provision for the camshaft retaining plate.
Sorry, I got the two mixed up, but the early blocks definitely do not have provision for the retaining plate.
The only time I've even seen a camshaft pre-load button was on an engine Neil's dad built.
ptschram
Well-known member
pdxrovermech said:
I've seen bent pushrods in a Rover engine twice. When AFI mistimed his cam and when I mis-timed MY cam
:ack:
ptschram
Well-known member
There are four blocks in my machine shop with no provision for attaching the retaining plate, hence the occasional use of the camshaft button.
ptschram
Well-known member
http://discoweb.org/forums/showthread.php?t=74056
http://discoweb.org/forums/showthread.php?t=41325
Here is a good one:
http://discoweb.org/forums/showthread.php?t=66777
Another good post from PT:
http://discoweb.org/forums/showthread.php?t=43959
http://discoweb.org/forums/showthread.php?t=51516
That's just a quick search. But I guess cam walking is not an issue. No, not at all...
Those pics PT posted are about as relevant as the shit I just took this morning. Of course those antique blocks do not have a thrust plate; they had a fucking distributor. Why the fuck would you need a thrust plate when you have the god damn distributor drive gear holding everything in place and preventing it from walking?
And what 3 trucks do you have a D&D cam installed in, PT? Do you even own a truck newer than 1948? Are these cams installed in a 1996+ Rover? I'm betting they are not or you would have not of made those comments. Every Rover I've EVER seen with a D&D cam knocks at idle. I doubt it's doing any damage at all, but it is annoying as shit.
http://discoweb.org/forums/showthread.php?t=41325
Here is a good one:
http://discoweb.org/forums/showthread.php?t=66777
Another good post from PT:
http://discoweb.org/forums/showthread.php?t=43959
http://discoweb.org/forums/showthread.php?t=51516
That's just a quick search. But I guess cam walking is not an issue. No, not at all...
Those pics PT posted are about as relevant as the shit I just took this morning. Of course those antique blocks do not have a thrust plate; they had a fucking distributor. Why the fuck would you need a thrust plate when you have the god damn distributor drive gear holding everything in place and preventing it from walking?
And what 3 trucks do you have a D&D cam installed in, PT? Do you even own a truck newer than 1948? Are these cams installed in a 1996+ Rover? I'm betting they are not or you would have not of made those comments. Every Rover I've EVER seen with a D&D cam knocks at idle. I doubt it's doing any damage at all, but it is annoying as shit.
ptschram
Well-known member
No, I do not daily drive any trucks made after 1996, my wife does though.
I do however, have experience with the very first camshaft that Mark modified, Gary bought it and hasn't had a problem.
Bruce Crower told me the cam profile would keep it from walking.
Maybe you could find someone to grind the groove for you if you think it's so important.
At the risk of attracting the attention and disdain of Mike Rupp, do we really care if the cam makes a slight noise? We bought a high-performance camshaft to make an engine do things it wasn't necessarily supposed to do, maybe, just maybe a little noise is an acceptable compromise.
I'm still waiting for you to disagree with me about the pushrods. In more than 40 years of wrenching, I've never seen the need to replace a pushrod without evidence of damage. Maybe you just drank the Kool-Aid of whoever was selling you parts you didn't need.
I do however, have experience with the very first camshaft that Mark modified, Gary bought it and hasn't had a problem.
Bruce Crower told me the cam profile would keep it from walking.
Maybe you could find someone to grind the groove for you if you think it's so important.
At the risk of attracting the attention and disdain of Mike Rupp, do we really care if the cam makes a slight noise? We bought a high-performance camshaft to make an engine do things it wasn't necessarily supposed to do, maybe, just maybe a little noise is an acceptable compromise.
I'm still waiting for you to disagree with me about the pushrods. In more than 40 years of wrenching, I've never seen the need to replace a pushrod without evidence of damage. Maybe you just drank the Kool-Aid of whoever was selling you parts you didn't need.
ptschram
Well-known member
ptschram said:
Mark gave me the same horseshit story about how the cam would not walk because it's constantly being screwed towards the rear of the engine. It's horseshit. His cams walk. They make noise. It's annoying as shit. It like having a collector gasket leaking.
Mark will, for an additional charge, make it so a thrust plate can be used. I find that to be bullshit. Why not just do it right in the first place? In this instance, where the OP was talking about using a 4.6 cam, I don't see any need for him to look at mark's 230 cam. The 4.6 cam is probably cheaper, it's made to fit, and he would not need the mandatory D&D timing set with the timing ring built in.
If this guy was wanting a "high-performance", as you put it, type cam, such as the 258 or larger, then sure, mark's cams might be a good thing. But I would still have it machined to accept a thrust washer. Why the fuck would I want to put another engine together knowing it's going to knock at idle? That would be like not installing the oil pan gasket on purpose because I know the engine is going to leak oil sooner or later anyway.
As for you push rod story. Push rods wear. That's why it says to put the push rods back exactly from where they came from in your Haynes Manuel post above. If you put a push rod from cylinder 8 in cylinders 1 position, the wear patterns on the rockers/push rods may not mate. That's because the rods have worn. Sometimes this will make a tick in the engine, other times it will not. But why fuck around at all? It's $100; I put that much in the fuel tank last week. It's not like these are $1,000. It's $100. For $100 I'll pay for the peace of mind. The same thing could be said about head-bolts. Some people have had good luck reusing head-bolts. Not me! Why would you even risk it? It's $90, just buy new ones.
If you are reusing push rods you're a hack. You may as well reuse the spark plugs, oil filter, main seals, and valve cover gaskets, too.
Shit, remind me to never buy a set of reconditioned cylinder heads from you. It's hard to tell what kind of corners you cut there.