Okay, So What Did I Do Wrong ?

Randystys

Member
66 El Camino 383 10.5/1 Tunnel ram Dual 450s 4 speed (there's another thread on tuning the tunnel)

Anyway, I had a Comp Big Muther Thumpr cam in there and was getting some flack about it being a cruiser cam lotta noise not much power...
So I switched it out to a Crower Ultra Beast 0917 per Grumpy's suggestion.
And now I can't get it started...
Thinking maybe it's a timing issue... backfiring and pooping not even trying to run.
I know the timing chain and gears are lined up "0" dot to dot... Double triple check...
#1 Piston TDC verify with bore scope and lifters being down...cycled a couple times to be sure... Pulled and replaced distributer 180 same backfiring...
Tried both positions twice...
Back to TDC #1 tried advance, neutral and retard timing and still same backfiring...
Doesn't even seem to "lock up" because of too much advance..??
What am I missing. ?
I've done this 100 times before and they always start up even if rough I can roll it in... But this time nothing...
 
there's a dozen possibility's
yeah I know you think its already been checked.....
Id start by verifying, and re-verifying

TDC on the damper and where the distributor rotor are both pointing,
in roughly the same place (cylinder #1 on the COMPRESSION STROKE)
and the intake valve rocker has recently returned to its valve seat)
Id back off the rockers until they click lightly at idle,
if the valves don,t fully seat because the lash or adjustment wrong your screwed
Id check the plug gaps are at about .043-.045
and the pistons not hitting the plug grounds
Id verify your getting ignition spark at the plugs
Id verify the fuel pressure is consistent at the carb or injector inlet
Id re check the firing order.(especially if its a 4/7 swap cam)
Id verify the rotor spins as the engines cranked and the firing order on the cap,
is in the correct order for the intended direction of rotation,
yeah we all have bad days, just find the issue with an isolate and test procedure

Did you degree in the cam or use the dot-to-dot install?
you sure would not be the first guy to use the wrong marks on the gears to set the cam timing
scan10001B.gif



CamTimingGear04.jpg

many guys don,t understand that on these multi key timing sets there areTHREE different letters,
on the crank gear and three matching keyway slots.

0 on the cam gear gets lined up with 0 on the crank gear, if the 0 crank key slot is used to index the cam at TDC

0 on the cam gear gets lined up with R on the crank gear, if the R crank key slot is used to index the cam at 4 degrees retarded from TDC

0 on the cam gear gets lined up with A on the crank gear, if the A crank key slot is used to index the cam at 4 degrees ADVANCED from TDC
http://www.superchevy.com/technical/eng ... index.html
sucp_0609_06_z+chevy_small_block+timing_gear_and_chain.jpg

CLOYESGR.jpg

crankgearvb.jpg


http://garage.grumpysperformance.co...ectly-and-get-it-to-last-cam-install-info.90/


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http://garage.grumpysperformance.com/index.php?threads/correctly-adjusting-valves.196/

http://garage.grumpysperformance.com/index.php?threads/finding-top-dead-center.967/

http://garage.grumpysperformance.com/index.php?threads/timing-tabs-and-indicators.1015/
 
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Damn it... You just answered my question...
Picture of the timing chain and gears... I used the dot to dot ( dot on bottom of big gear) with #1tdc...
Should have been dot at top of big gear.. as shown in the picture...
Missed it big time oh well easy fix thanks for the reminder...
What was I thinking... ?
 
But wait a second...
Even if I set it at #1 TDC with the dot at the bottom of the big gear in one revolution of the lower gear I will still end up with dot at top of big gear and small gear and #1 TDC
Correct..?
So I don't really have to pull the timing cover..just yet...
I just need to confirm compression stroke TDC..and damper 0. And set distributer on #1 from there (which I've done)

So I think I still need to look at something else..,??
 
With the crank turned to TDC compression stroke, with lifters on the bottom, where are the lifters on #6 cylinder? They should be even, or VERY close but a little higher than cylinder 1.
If you made the common mistake of lining up the dots--big gear dot down, that is #6 firing. Or 180 out.
Recheck the firing order of the plug wires.
 
With the crank turned to TDC compression stroke, with lifters on the bottom, where are the lifters on #6 cylinder? They should be even, or VERY close but a little higher than cylinder 1.
If you made the common mistake of lining up the dots--big gear dot down, that is #6 firing. Or 180 out.
Recheck the firing order of the plug wires.
So I should be able to "fix" that by running my distributer 180 out correct?.. I did try that and didn't have any better results...

I'm going to try resetting the lifters... I usually set them cold so they just finger spin and lock them down...them instructions that came with the cam said finger tight and then 1/2 turn more... I thought/it felt to be a bit much...
I'll try that next...
 
well? any progress on the isolate and testing?
(I REALLY WISH I WAS LOCAL)
 
The finger spinning method sucks - especially when there is no oil in the lifters.
Watch for the plunger to break free of the snap ring or wire clip on the lifter.
Of course, each lifter must be done on the base circle of it's cam lobe.
 
well? any progress on the isolate and testing?
(I REALLY WISH I WAS LOCAL)
I was working today I'll be out in the shop tomorrow, Sunday and will report what works or didn't work.

Yeah it'd be nice to have a second eye or ear on it to help narrow it down.
 
The finger spinning method sucks - especially when there is no oil in the lifters.
Watch for the plunger to break free of the snap ring or wire clip on the lifter.
Of course, each lifter must be done on the base circle of it's cam lobe.
This is the first thing on my list to try tomorrow.. not sure I want to pull the intake off to set the lifters at this point, but now they are full of oil...and the break in grease is wore off so I should get a good feel for setting them...
It will also give me opportunity to verify my cam timing in on...
 
Okay we fixed it... meaning the advice you gave me here helped... And I got it running...

Spark checked okay
Plugs gaped okay
#1 TDC check
Damper on "0" check
Fuel pressure check
Firing order wires check
Valve lash messed up <<<<

Like I said in my first post I didn't like the way it felt when I did it according to the instructions that came with the cam and lifters...
" Get them to spin tight and 1/2 turn more"
But they were cold and dry and had a layer of grease on them so they just didn't feel like they usually do when going to definitive tight spin... So I think/know I over tightened them... The other clue which I didn't mention and should have is it was popping out the exhaust as well as the carb....now I can see the overly tight lifters doing that....

So now that they're full of oil the came to a nice tight spin, I didn't do the extra 1/2 turn and I do have a little ticking going on, nothing serious but after break in I'll reset them one more time...

But thanks again for helping me through this, I was getting frustrated and ready to pull the whole front end off again which would have been a waste of time other than I might have stumbled on resetting the lifters as a by product.

Running good, sounds good, a bit more authoritative than the Mutha Thumpr that was in there... Looking forward to tuning it in...
 
YEAH, THATS A VERY COMMON MINOR SCREW-UP,
MOST PEOPLE MAKE ...one that many people have made,
or some other mistake on the list,
AT LEAST ONCE.
GLAD YOU WORKED THROUGH AND GOT IT RUNNING:D
chalk it up to paying your dues and learning the procedure

the key here is in any person
,just mentally stepping back and thinking things through!
you first isolate the problem,
by verifying all potential options, or changes
were correctly done and parts correctly installed,
then you do whats required to fix that problem.
once you find out what was missed, skipped or not done correctly
you don,t just randomly start swapping parts
 
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