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Hmmm, loss of power won't hold speed...

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reamer

Re: Hmmm, loss of power won't hold speed...

OK will do that next.
Ill have my assistant (daughter) watch the dizzy!

1986 F-150 Flareside 4x4, 351, 4-v, ZF5 speed. AC, Cruise, Tilt, Slider, Digital clock, Radio, Lariat seat, Pwr doors/locks

ArdWrknTrk

Re: Hmmm, loss of power won't hold speed...

Administrator

You can do it all from right on top.

Get a 4" extension if your 1/2" drive deep well is too short.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

reamer

Re: Hmmm, loss of power won't hold speed...

In reply to this post by ArdWrknTrk

Well me thinks I found the issue.....

I went out and grabbed the 15/16" socket,
I rotated the crank counterclockwise till the rotor started to move.
Since I was on top, I took where the ratchet handle lined up with the radiator shroud, I put a mark on the shroud.
Now I rotated clockwise, until the rotor started to move, Then I marked that spot.

I have just over 5 linear inches rotation of the crank till the rotor moved.

The shroud measures 22" in Diameter.
= just over 69" in Circumference.

5 linear inches on a circle with a 69" circumference = 25.31 degrees of play.....

Why does this idle fine? because of no load? do a WOT and she screams nicely...

1986 F-150 Flareside 4x4, 351, 4-v, ZF5 speed. AC, Cruise, Tilt, Slider, Digital clock, Radio, Lariat seat, Pwr doors/locks

ArdWrknTrk

Re: Hmmm, loss of power won't hold speed...

Administrator

See my recent postings in the wdydtytt for what you're about to get into.

Man, that sucks. It's a lot of work to do it right.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

ArdWrknTrk

Re: Hmmm, loss of power won't hold speed...

Administrator

In reply to this post by reamer

Put the timing light on it and snap the throttle open.
Watch the timing marks as the engine returns to idle.

It should be really smooth as the advance retreats.
If it seems jittery, that is the chain flailing around.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

Gary Lewis

Re: Hmmm, loss of power won't hold speed...

Administrator

In reply to this post by reamer

Yes, you probably found the problem. But, it may not be as bad as you think. I say that because most of my ratchets and breakovers have enough slop in them to account for many degrees. So to be accurate you'd need to take the slack out of the wrench in the same direction both times before marking the shroud.

But do as Jim suggested and see what happens when you snap the throttle closed. However, you should plug the vacuum advance or it may cause some movement.

And Jim's travails are well documented. However, what he didn't have was a broken off bolt 'cause he went with stainless bolts last time. In my experience the Windsors are really bad about breaking bolts. So, don't pull it down until you have the time to drill out a broken bolt - and go find a replacement.

Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

ArdWrknTrk

Re: Hmmm, loss of power won't hold speed...

Administrator

When the valve events get too out of sync from the pistons approaching and retreating from TDC, charge gets forced back out causing carb spitting, and the spark happens too late to do anything but follow the piston down.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

ArdWrknTrk

Re: Hmmm, loss of power won't hold speed...

Administrator

This post was updated on .

In reply to this post by reamer

Shroud is centered on the water pump.
The breaker is on the crank.

You need to use the radius of the breaker handle to the shroud lip to determine rotation.

I think you're reading ***WAY*** too much.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

ArdWrknTrk

Re: Hmmm, loss of power won't hold speed...

Administrator

This post was updated on .

In reply to this post by Gary Lewis

Maybe source some stainless bolts to put it back together!

I use Loctite PST on the threads of all those bolts through the timing case, and water pump too.
Can't seize if corrosion can't get to the threads.
And this anaerobic sealant does not really affect breakaway torque.

One of these two is your friend for bolts in the timing case or water pump.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

Rembrant

Re: Hmmm, loss of power won't hold speed...

In reply to this post by Gary Lewis

Gary Lewis wrote

But, it may not be as bad as you think.

I agree Gary. Also note that he rotated the crank CCW first until all the slack came out, and then rotated the crank CW. Even if everything is fine, there'd be a lot of slack to switch from CCW to CW. When I took my 302 apart, the factory chain was really loose, and that was with only 30k miles on it. Might be hard to tell in the picture below, but that chain was really loose.

1994 F150 4x2 Flareside. 5.0 w/MAF, 4R70W, stock.
1984 F150 4X2 Flareside. Mild 302 w/ 5spd. Sold.
1980 F150 4X4 Flareside. 300i6 w/ 5spd. Sold in 2021.
1980 F100 4X2 Flareside. 351w/2bbl w/NP435. Sold in 1995

ArdWrknTrk

Re: Hmmm, loss of power won't hold speed...

Administrator

Ugh
Plastic....

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

reamer

Re: Hmmm, loss of power won't hold speed...

So I did the test again, this time I cleaned off the harmonic balancer timing marks, rotated the crank Counterclockwise two complete rotations to ensure the rotor was under tension, then stopped rotating the crank with the pointer at the mark of 30 degrees BTDC.

Then rotated with a breaker bar clockwise until the rotor just started to move, and looked at the harmonic balancer, it is now at 10 degrees BTDC. This took out any play in the breaker bar.

So I have 20 degrees O' play.

Enough for surgery?

Always said to myself, if it needs repair, pull it and do a complete rebuild... But with 150 psi per cylinder, AND dealing with the falling apart cement foundation, I think just do a chain, front oil pan seal, water pump...
Thoughts?

1986 F-150 Flareside 4x4, 351, 4-v, ZF5 speed. AC, Cruise, Tilt, Slider, Digital clock, Radio, Lariat seat, Pwr doors/locks

Gary Lewis

Re: Hmmm, loss of power won't hold speed...

Administrator

Yes, that's a problem. And yes, I'd do the "chain, front oil pan seal, water pump..."

Gary, AKA "Gary fellow": Profile

ArdWrknTrk

Re: Hmmm, loss of power won't hold speed...

Administrator

"front main seal" and a speedisleeve.

The timing gasket set WITH is only $6 more (in my case) and I'd rather be looking at it than looking for it....

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

reamer

Re: Hmmm, loss of power won't hold speed...

Thinking of going with Jasper crate engine, the "Stock Performance Model." seems this would be a faster-cleaner way, and I may pull the ZF-42 for a rebuild too, The ZF shifts fine, stays in gear, (even in reverse) but a Idle is sounds like massive rod-knock, (push clutch in and all is quiet), and a crap load of chatter in the sweet spot between acceleration-load and deceleration-load..
Thoughts?

1986 F-150 Flareside 4x4, 351, 4-v, ZF5 speed. AC, Cruise, Tilt, Slider, Digital clock, Radio, Lariat seat, Pwr doors/locks

ArdWrknTrk

Re: Hmmm, loss of power won't hold speed...

Administrator

I think your engine has good compression and more miles to go before it's clapped out.
Timing chains are a wear item, and need changing.

I think all Zf's clatter at idle in neutral.
"Rollover" is always there unless you run it over full or really heavy gear oil (which is no good for the synchro's)

Knocking when lugging is excessive end play, and the helical gears banging the shaft into the thrust bearing.
Not the end of the world.
My truck has been doing it since I swapped the Zf in.
All will do this. It's a matter of how loud.

You have a truck gearbox.... In a truck.
That's the way it's going to behave.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

Gary Lewis

Re: Hmmm, loss of power won't hold speed...

Administrator

I agree. A ZF5 is a noisy tranny. Mine worked pretty well with bad synchros and a broken reverse gear, which just meant that shifting had to be done slowly and there were times it would NOT go into Reverse w/o moving the truck forward.

But a rebuild is expensive. I paid a pro ~$1000 for a complete rebuild on mine, inc parts. But he was moonlighting and using the shop's facilities, so I got a good deal. IOW, it would have been more had it been done "professionally". However, I would have then had a warranty, so I'm not sure which way would have been better.

Gary, AKA "Gary fellow": Profile

ArdWrknTrk

Re: Hmmm, loss of power won't hold speed...

Administrator

9/10 not going into reverse is a clutch drag issue.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

Gary Lewis

Re: Hmmm, loss of power won't hold speed...

Administrator

Yes, but this was the 1 out of 10. It wouldn't only do it every once in a while, and then it would NOT go w/o moving the truck. So I learned to never, ever park where you couldn't roll forward.

Then when the guy took it apart he discovered the reverse gear was broken. According to him that would create those symptoms.

Gary, AKA "Gary fellow": Profile

reamer

Re: Hmmm, loss of power won't hold speed...

The chattering with no load at highway speeds is Normal?

1986 F-150 Flareside 4x4, 351, 4-v, ZF5 speed. AC, Cruise, Tilt, Slider, Digital clock, Radio, Lariat seat, Pwr doors/locks

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