455 won't start / 1970 Toro

[pr129tbird]

I've found that NOBODY i've ever gone to can rebuild a carb properly!! They typically ALWAYS screw up something that the car either bogs under acceleration or it dosnt idle right or BOTH! I think they re-adjust the float which was fine and they get it out of wack! I dont touch the float if the carb was running ok and had power under full throttle. I leave it where it was!

[Eightballz]

just bought an rebuilt carb cause my old qjet had worn out throttle plate bushings....and came off a 1974 pontiac.

well the rebuilt carb didnt seem to need a complete overhaul...will fix the float bowl level issue tomorrow...i'll check the other specs too and re-calibrate if necessary.

can put it back on the engine next weekend

[Eightballz]

So...the carb is back on the engine....can you tell whats the problem? All vacuum ports are plugged.

http://youtu.be/A-vPvnS15wA

http://youtu.be/W11B9BD_eY0

[Roadscholar]

Hi,

My 2 cents, another common problem with Toro carbs is leaking well plugs...... see if your bottom gasket is soaked with gas. Gas may be leaking directly out the bottom from leaking lead plugs in the casting.


Clyde D. Cummins TOA #56

[Eightballz]

ok guys...i've checked the TDC of the first cylinder...the mark on the damper was around 6° before....so since the shop manual says 5°-7° i guess its ok.

then i checked the spark again which was strong enough

tried to run the car without fuel and a shot of ether after i disconnected the fuel line from the pump....i saw that it was dry...gas tank was empty...so i got some fresh gas. the car ran with that ether-shots.

after that, i checked the dwell angle again i adjusted the points.

then the car had a nice and smooth idle ...and i could rev the engine a bit without stalling....engine was cold....distributor vaccuum disconnected and plugged.

i let the eninge warm up till operating temp. ...but then the car began to stall and it died after...dont know..about 3-4mins...at operating temperature the car reacts like in the videos below...sloppy idle and bad response to gas pedal movement. (http://youtu.be/dfZohMWj2m4) ...what you cant hear on the video, is that short "knock sound" before the engine starts...

at least i fixed the flooding issue so the carb is dry outside and there are no more seas of fuel inside the intake manifold...so i guess that leaking drain plugs are not causing the problem...

next thing i wanna do, is to get myself a dwell meter, rpm meter and a timing gun...next try in 5 days

[Schurkey]

ok guys...i've checked the TDC of the first cylinder...the mark on the damper was around 6° before....so since the shop manual says 5°-7° i guess its ok.

You have #1 piston at TDC but the mark on the damper aligns with 6* mark of the timing pointer??? The damper has slipped and is now ruined. You have 6 degrees less initial timing advance than you think you have.

You must set dwell BEFORE adjusting timing. Adjusting the dwell changes the timing.

[Eightballz]

ok guys...i've checked the TDC of the first cylinder...the mark on the damper was around 6° before....so since the shop manual says 5°-7° i guess its ok.

You have #1 piston at TDC but the mark on the damper aligns with 6* mark of the timing pointer??? The damper has slipped and is now ruined. You have 6 degrees less initial timing advance than you think you have.

You must set dwell BEFORE adjusting timing. Adjusting the dwell changes the timing.

yeah..some guy told me it should read 0° ..so i guess the damper is trash

i dont really know if it was the compression stroke..what should the mark on the damper read if it was the exhaust stroke...?

i didnt touched the timing....gonna get me a timing gun first

[Schurkey]

ok guys...i've checked the TDC of the first cylinder...the mark on the damper was around 6° before....so since the shop manual says 5°-7° i guess its ok.

You have #1 piston at TDC but the mark on the damper aligns with 6* mark of the timing pointer??? The damper has slipped and is now ruined. You have 6 degrees less initial timing advance than you think you have.

You must set dwell BEFORE adjusting timing. Adjusting the dwell changes the timing.

yeah..some guy told me it should read 0° ..so i guess the damper is trash

Or you have the wrong timing pointer, or you weren't precise in finding "true" TDC.

i dont really know if it was the compression stroke..what should the mark on the damper read if it was the exhaust stroke...?

Exactly the same thing. TDC is TDC. There's one at the end of the compression stroke, and one at the end of the exhaust stroke...but both of them should read "0" on the damper/timing pointer.

i didnt touched the timing....gonna get me a timing gun first

You re-set (changed) the dwell. Therefore you changed the initial timing.

[pr129tbird]

OOOOPs sorry about my post! LOL I said Air, Fuel and gas! LOL I am sure you all knew what I meant Air, Spark , and Gas/fuel. Sorry perhaps I shouldnt post AFTER drinking MY "fuel' Run N Coke LOL

[Eightballz]

so thats the result of the last days...could borrow a really cool timing light which was adjustable and it was able to show dwell angle and RPM too.

http://youtu.be/n5NatFAY16o

http://youtu.be/QoxMhmgjgNs

http://youtu.be/WIMOjvdbBqc

i set the dwell angle again and the timing referring to the shop manual...after that i adjusted the fast and slow idle ...and mixture screws.

last problem i have is shown in the last video...if you rev the engine slowly the engine stalls a bit and the RPM drops...i get the feeling that the acc. pump isnt working properly....but it has nice strong shots of fuel when pushing the rod of the pump. thats only at part throttle i guess...when you rev it with full throttle its not that bad.

you can read it from the vac gauge when vac drops to zero the engine stalls.

vac advance is connected to ported vac

It seems that the engine has lack of fuel when throttle plates passes the off idle holes.. do you guys think that this can be caused by a low float Level? Or maybe mixture screw adjustment effects off idle operation?

how i set mixture screws:

- turn screw in till seated and turn it out 6 full turns
- raise idle RPM to 675
- turn both screws simultaneously in, till you hit 600 RPM (which is the slow idle RPM specification)

vac gauge reads around 12"/Hg at idle ..shop manual says 10-13" at start

acc pump shots fuel when i rev the engine

so..what can cause that off-idle stumble?

P.S.: sounds menacing when secondaries open up