Stroker Renewal?

[Frank Z]

Did you get my voicemail?

 

[xj-grin]

Did you get my voicemail?

I did now, not sure how I missed your call since my phone is on the desk in front of me...

I don't think I'll have time this afternoon to go see Lynn - given how busy they are, even a trip to pick up parts always takes the better part of an hour... If its cool with you, I'll swing by your place tonight on the way home...

Funny story, searching for girdle issues and I came across a stroker build thread by some FrankZ dude on "polkaudio.com" who had the same girdle issues.

 

[Frank Z]

Sure, come on by.

 

[ADam J]

? :eyes:

 

[xj-grin]

busy -- maybe tomorrow evening I can tear into it... I'm still leaning towards timing calibration and a clunk on the girdle...:eye:

 

[xj-grin]

SO --- I pulled the pan last night, turned it over briefly to look for interference with the girdle, found none -- considered with Frank that while there might be no contact with the girdle simply turning it over, the force of combustion when running could deflect stuff just enough to contact -- ran it with me under it taking an oil shower for about 5 seconds and....






























not only did I see no contact, it didn't make any knocking noise at all. :wierd: F#$%^ trucks - never make the "sound" when you take it to the mechanic... Anyways, since it is already disassembled, I double (triple ) checked all the torque on the main bearing caps and rod bearing caps, no issues, and will reassemble with an extra spacer on the girdle just in case it is actually contacting tonight. I also noticed a couple of bolts holding the inspection cover on were loose, so those got snugged up -- perhaps there is an outside chance that my knocking was the inspection cover (since the sound was clearly way back in the engine, and at times sounded like it might of been in the bell-housing), but I seriously doubt it. I'll put the oil pan back on tonight and fill her back up, double check the torque on all the valve train components (i.e. rockers), cross my fingers and move on to the timing issues... :|

 

[xj-grin]

bottom end back together... still noisy. So Yella swung by this afternoon and lent his seasoned ear. While he agreed it sometimes sounded low (redemption for FrankZ and I), he thought it had the tone of valvetrain noise. We pulled the valve cover, and WALA (?), bent pushrods.

So, replacing the pushrods is easy enough, but first I want to figure out why they are bent. My new Crower cam is actually milder than its Crane predecessor, having less lift. I am using the same rocker arms, springs and rods as pre-rebuild. I do have new lifters - Crower cam-saver hydraulics, and at this point we are thinking I either have a bad lifter, or improper lifter pre-load...

This is where we need some clarification -- how could my lifter pre-load be off when the entire valvetrain/head/springs/rockers/rods haven't changed? Little help here...

 

[YELLAHEEP]

I still think that it has to do with the combination of the larger lobe cam and the stiffer valve springs. Those push rods looked like stock ones, and I'm betting that they just weren't up to snuff for the added stress.

You mentioned that this new head should actually be "thicker" since it's not been milled like the previous head was. And given that the cam is a bit less aggressive than the previous cam..... you should have plenty of movement (meaning the push rods aren't likely to be too long).

Does Frank have another set of push rods laying around? Maybe swap the bent ones out for some straight ones and let the engine idle again for a minute or two and ensure that the engine noise is gone - that'd answer your noise source question for certain, then you could feel better about looking into some heavier duty push rods and ensuring the valve springs are allowing for enough travel. (Hopefully the springs (either inner or outter) aren't being completely compressed to where the coils are all mashed together when the valve is being opened) if ya dig what I'm saying.

Just seems to me that the combination of stock, used push rods in combination with a beefier cam and stiffer valve springs would put a lot of stress on those rods. :thumbup:

 

[Frank Z]

Actually Chris may have found the problem. I'll let him do the splainin'......

 

[xj-grin]

I'm convinced it is a lifter pre-load issue. As is typical, I soaked my lifters overnight in oil and then loaded/unloaded them by hand with a pushrod while submerged prior to installation -- some reading yesterday indicates this can actually act to make the lifters act "solid", as opposed to priming them, which would then result in 0 preload, and effectively longer pushrods. I'll be testing preload on all of the lifters with the unbent rods, and perhaps ordering up a couple new lifters if I have one seized -- unless anyone has good lifter bleed down suggestions...:confused1

 

[Hypoid]

Pull them for an clean and inspect.

I know of an old A&P mechanic on another board who takes new lifters from the box, disassembles and cleans them in mineral spirits. His observation is that he ALWAYS finds debris from the manufacturing process inside new lifters. On a side note, he always spends big $$$ on premium brand parts, to find trash inside.

When you had the bottom end open, did you make it a point to check the cam lobes for excessive wear? Perish the thought :gag:, but, not enough preload will let the pushrods un-seat and contact the side of the lifter. Never mind how I know this...

 

[YELLAHEEP]

Well, I definitely don't do a whole lot of engine buildin'...... but I'd never heard of a hydraulic lifter NOT bleeding down, holding oil pressurized in itself like that.

If it was in fact holding pressurized oil and not bleeding down...... Why was I able to spin those bent rods after the engine ran? If it was acting like a solid lifter - wouldn't everything have been tight?

The reason I bring that up is that just a couple minutes after Chris ran the engine to have me listen to the sound, he removed the valve cover and when looking at the rocker arms - all of them were "relaxed". None were still pressing down on any valves holding the valve open. Only 2 rods were tight enough that I couldn't spin them with my fingers which - to me - indicated that the lifter was sitting on the high-side of the cam lobe.

I'm just asking this for my own education. If ya find anything on the web about the pre-load issue, post it up - I'd like to learn about it.

 

[xj-grin]

Well, I definitely don't do a whole lot of engine buildin'...... but I'd never heard of a hydraulic lifter NOT bleeding down, holding oil pressurized in itself like that.

If it was in fact holding pressurized oil and not bleeding down...... Why was I able to spin those bent rods after the engine ran? If it was acting like a solid lifter - wouldn't everything have been tight?

The reason I bring that up is that just a couple minutes after Chris ran the engine to have me listen to the sound, he removed the valve cover and when looking at the rocker arms - all of them were "relaxed". None were still pressing down on any valves holding the valve open. Only 2 rods were tight enough that I couldn't spin them with my fingers which - to me - indicated that the lifter was sitting on the high-side of the cam lobe.

I'm just asking this for my own education. If ya find anything on the web about the pre-load issue, post it up - I'd like to learn about it.

Hypoid -- its a new cam as well, so no lobe damage (at least there wasn't...:shocked

Troy - I think that rod that was most bent would have been really tight, if it wasn't bent, which effectively took the tension off. I'll post up after I check the preload on the lifters, although likely not today with the superbowl and all... If any are stuck/collapsed, they'll be getting replaced... and Hypoid, I wouldn't have a clue how to disassemble/reassemble a hydraulic lifter. :confused1

 

[old_man]

I'm convinced that many of the cam failures are really from not checking for spring binding with a new cam, lifters, valve job, and milled head or block.

 

[xj-grin]

I'm convinced that many of the cam failures are really from not checking for spring binding with a new cam, lifters, valve job, and milled head or block.

I agree -- in my case the old cam had higher lift, and the old head was decked. I am using the same springs from the old engine (I believe they are from Crane), so if anything, they should compress less in this set-up than the old, and binding shouldn't be an issue (it never was before...) -- unless my understanding is completely backasswards, which is of course a distinct possiblity :laugh:

 

[ADam J]

Chris,

were you using the old pushrods? Just as an FYI, they were not stock length... When I assembled it originally, I measured the pre-load before firing it up, and it was off quite a bit. so I replaced the push rods with an adjusted size ( shorter I think)... It's been a while...

I would think that checking the pre-load would be the correct course of action.

 

[xj-grin]

Thanks for chiming in, Adam -- I measured the pushrods this morning and can confirm your memory that they are shorter -- stock is 9.65, these are 9.56 or so... I'm assuming your rods were shorter because the head was decked, but since the new one isn't stockers might be in order. I'll confirm it with a preload test. Let me know if you have any other memories!! :cheers:

 

[Hypoid]

I wouldn't have a clue how to disassemble/reassemble a hydraulic lifter. :confused1

Pretty straight-forward actually.

Since the engine has sat, you should be able to push down on the pushrod with your hand and get a little movement from the plunger. If not, it's time for a look-see.

Although, I think you already found the problem.

Here are a thousand extra words:

 

[ADam J]

Let me know if you have any other memories!! :cheers:

.10 short sounds about right.

Could it be that they are too loose? Hence why Yella was able to spin them so easily? You are using a different head now right? Obviously new lifters and cam are enough to warrant the pre-load test...

Thats all my memory's got right now... I'll chime in if something else rattles loose...

 

[Frank Z]

Any progress Chris?