After doing a lot of work on the top end of a 455, I am having trouble getting it running. Life got in the way so this whole process has taken me about a year. I have some other threads out there on the project, but they are fairly old.

What's been done:
C-heads rebuilt, new head gaskets (thick felpro blue)
New timing set/cam (mild erson from cutlassefi)/lifters
Rebuilt q-jet (stock build from sparky's)
New water pump (flowkooler)
Harland sharp roller rockers (pedestal style/adjustable) adjusted preload to 3/4 turns on the adjusting cup past no lash (their tech said this equates to about 30 thousandths)
Dropped oil pan, cleaned out pickup.

Cam was degreed in per the sheet, oil was primed, confirmed top dead center on compression stroke for #1 cylinder and set static timing at approx 9 before tdc, advance is connected to manifold vacuum. Filled carb bowl with about 1/4 cup of gas and pumped the pedal a few times. Car fired up immediately and ran (poorly) for about 5 seconds and then died. Further attempts to pump the pedal and turn the car over failed to get it started. I did not want to crank the motor excessively as this first start will also be breaking in the new cam.

Initial observations:
- Motor pulls almost no manifold vacuum while turning over (maybe 2 inches). Not sure if this is normal. Did not occur to me to plug all manifold ports to eliminate other potential leaks.
- Engine seems like its turning pretty fast with the starter (700-800 RPMs according to the tach). Maybe rockers too tight leading to bad/no compression? Don't have a compression test kit, could get one, but don't want to spend tons of time turning it over anyway because of the new cam. Did turn the motor over by hand with a breaker bar and it was VERY stiff, so there is some compression! If valves were hanging open, I would expect backfiring through the carb? There was none of this.
- After all the cranking I did (<25 seconds or so total) I found there was still no gas in the upper fuel line. Maybe after all that time on the bench the diaphragm in the fuel pump sprang a leak?
- Confirmed spark with a timing light.

Anyway... I'm off to O'Reilly to look into a new fuel pump so I have it on hand.

Where to begin?

Any suggestions appreciated!

 

Hi roth

definetly plug all vacuum ports that arent used first

right off the bat id say the fuel just may not be pumped to the engine yet. It might be as simple as the gas in the carb ran thru already.

I cant comment on the cam break in.

you could try a gas can right off the fuel pump to get fuel there quicker.

also be sure the fuel pump is on the eccentric correctly.

you will probably have to turn the distributor and or tyrn up down idle to keep it running.

when cranking, generally speaking i crank for 5-6 seconds then give the starter a rest and pump the gas a couple times then crank for 5-6 seconds etc. when my car hasnt been run for a couple days it takes 2-3 iterations of that to get going

dean

 

Is there gas in the tank???

 

Very important step.

 

Hugely important!

But yes, indeed, there is gas in the tank.

My main concern is around the manifold vacuum/valve lash/compression, any thoughts there?

 

Well if you don't see fuel squirting into the venturies when you pump the throttle or even the accelerator pump, obviously thats a factor.
I'd also put a timing light on it to check spark and rough in the timing, obviously no spark is a factor.
If you're running points, sitting after burning the contacts will introduce resistance.
Sounds like everything is in order.
We use a 6 gal outboard can and line to prime engines and troubleshoot delivery.
Interested to see what you discover here even if its silly.

 

Fill the float bowl through the vent tube. Use a small funnel or a syringe. That should give enough fuel for the engine to run long enough to get fuel pulling through the pump.

 

Double check that distributor after you verify spark and fuel. When I brought my engine back to life after a timing chain, distributor, and manifold gasket refresh I would have bet my last dividends check I had the distributor in correctly--I was wrong it was 180 degrees off.

 

Don’t forget counter clockwise on the dist spinning

 

Thanks for all the input: It was the fuel pump!

I swapped it out, refilled the carb and it fired right up. Cam break-in seemed to go smoothly. Any surefire way to reassure myself I didn’t flatten any lobes?

I also disconnected everything from manifold vacuum and capped everything to eliminate vacuum leaks anywhere else in the system (brake booster etc.), not sure if that helped or not, but for the time being, it’s a big step in the right direction!

 

glad you got it going...
I guess a comp check is one way to check the cam...
im surprised you found a fuel pump in stock... at the begiining of the season mine went and no store, oriellys, advance, autozone, fisher, etc in 20 miles of me
had either pump in stock. i ended up putting a used one on that i had till i got a new one ...(still have the used on on there )

 

Ha! There was exactly one on the shelf in the greater Worcester area!

But, the way parts are these days, I'll bet your used pump is still going strong when my "new" one has long since flown across my garage into the garbage can!

 

If you lubed the cam well on assembly it is fine, drive on and enjoy!!!

 

So turns out I do have a few issues after all. While tuning, I noticed a tapping on the driver's side of the motor and (after calming down a bit) found that my roller rockers are not contacting my baffles on that side (less so on the passenger's side).

I did double gasket, but I suppose I will have to peen the baffles a bit as well for clearance.

But, I also noticed that a couple of my pushrods are contacting the heads as well and rubbing quite a bit. What should I do here?

The way it was explained to me by the tech at HS, there isn't a ton of room for adjustment. The pedestal bolts to the heads and things are locked in. All the adjustment is at the pivot point over the pushrod so it doesn't really work the way a polylock would. You can optimize for pushrod length to allow you the most room for adjustment of valve lash, but otherwise, it is what it is. I did measure the pushrods rods and opt for slightly longer ones, but I've also never done this before...

Any suggestions?

 

Im no help but are the pushrods the original diameter ? I recall one member had some larger diameter pushrods that had an interference fit.

 

passenger side

#5 cylinder intake

#5 cylinder exhaust

#5 cylinder contact patterns

drivers side rockers

more drivers side rockers

driver's side rocker cover

 

https://classicoldsmobile.com/forums...-3-8-a-115251/

heres the thread i was thinking of

 

They are 5/16, same as the ones I took out. Some of the old ones also had a little evidence of contact as well.

 

I was right im no help!! The old ones rubbed to huh?

idk do they need guide plates ?

 

Just a couple of the old ones, and only slightly, like the less bad one I showed above. And thanks for chiming in, Dean. You're always helpful, even when you're not!

Being I haven't done this before, I'm just not sure what the best course of action is: I could create the clearance I need pretty quickly with a file, but if the real solution is longer or shorter pushrods, and I've f'd up along the way, I'd love to know.

I did find another thread, but the OP there was using different rockers and Harland Sharp rockers actually fixed his problem: https://classicoldsmobile.com/forums...s-52562/page2/

And these guys actually say excessive pushrod clearance can be a bad thing:
http://www.mantonpushrods.com/Pushrod-Info.html

"Do not allow over clearancing for the pushrod. This may cause the pushrod to move around or deflect more than needed. Clearance of .010 at the closest point, wherever that may be during its complete cycle is sufficient. The cylinder head and engine block can often be utilized like a big guide plate and dampening device, which stabilizes the pushrod. Just make sure that there is no interference problems when turning the engine over on the engine stand."

I don't know... since most of the obvious issues are around cylinder 5, I'm going to check my settings there tomorrow morning and work my way out to see if anything obvious comes up. Then I might put in a call to Harland Sharp and the machine shop that rebuilt the heads on Monday and see what they advise.

This problem does seem to come up on the chevelle and ford forums periodically and folks are pretty evenly divided between "leave it" and "file it."

 

I have the same set up.
no issues with pushrods, but I have guide plates.
I run my rockers loose. At 3/4 past lash compared to 1/4. Makes a huge difference.. im my car atleast.
my stock covers,, baffles removed.

 

Nice! Thanks for the reply!

Did you run stock pushrods or measure for new? HS said the kit should work with stock length, but this didn't seem to give me enough room for adjustment. The ones I ended up with after measuring were only a little longer @ 9.560" vs 9.546" which I think is stock length.

Maybe I'm missing something: you run them at 3/4 or 1/4? Wouldn't 1/4 be the looser of the two?

I may need to go that route, did you run thick or double gaskets?

Sorry for all the detailed questions, I'm very new to the whole adjustable rocker thing.

 

rothlane, I noticed a couple of the members stated they use guide plates, do not use guide plates with the "pedestal" style rockers! If peening the valve cover baffles provides clearance, I would not cut the baffles; thick gaskets always worked for me. I have not seen the pushrod clearance issue when 5/16" pushrods are used and the rocker ratio is the stock Olds 1.6 to 1. Is it possible that you have a different ratio rocker arm kit?