The V8 Owners Forum -

Hi,

I need your expert help on getting my Rv8 3.9 started. I have replaced the EFI with an edelbrock carb, but everything else is standard. I have a new coil, new plugs, and new leads. There is fuel to the carbs and spark at each plug. I suspect the timing is wrong, as I had to rotate the distributor by 180 deg to fit the inlet manifold thermo housing properly. I re-timed it by setting to TDC and shifting the plug leads around in firing order from No.1

It fires and seem about to catch, but never does. Occasionally I get a big pop from the carbs and a small flame/puff of smoke from the air-intake - raised the heart rate!. Just before the battery died I gave the distributor a small turn clockwise and it made a difference. It caught, and fired up, but very lumpy, on 1/3 thottle. As soon as I dropped the throttle to idle it stalled and another pop from the air-intake.

Should I be limiting the air intake by engaging the choke, and/or should I leave the vaccum advance on or off?

So, while it's charging I thought I'd gain some knowledge from you smart chaps!
Thanks
TimN

The way you describe the big popping makes me think it's predominantly a timing issue IMHO, or leads on the wrong plugs. Go through and check everything thoroughly.

But also, when you fitted the carb, what did you do RE the fueling? The carb wants about 4 PSI fuel pressure if I recall. I would say the fuel injection pump would be way too high.

timnutt wrote:Hi,

I need your expert help on getting my Rv8 3.9 started. I have replaced the EFI with an edelbrock carb, but everything else is standard. I have a new coil, new plugs, and new leads. There is fuel to the carbs and spark at each plug. I suspect the timing is wrong, as I had to rotate the distributor by 180 deg to fit the inlet manifold thermo housing properly. I re-timed it by setting to TDC and shifting the plug leads around in firing order from No.1

It fires and seem about to catch, but never does. Occasionally I get a big pop from the carbs and a small flame/puff of smoke from the air-intake - raised the heart rate!. Just before the battery died I gave the distributor a small turn clockwise and it made a difference. It caught, and fired up, but very lumpy, on 1/3 thottle. As soon as I dropped the throttle to idle it stalled and another pop from the air-intake.

Should I be limiting the air intake by engaging the choke, and/or should I leave the vaccum advance on or off?

So, while it's charging I thought I'd gain some knowledge from you smart chaps!
Thanks
TimN

The vac advance does not work very well with the Eddy carb so I'd leave it off. Also if you do use it and connect it to the non-timed port on the carb you will end up running a lot of advance at tickover

If it was my engine I'd take the rocker cover off the odd bank of cylinders (1357), I'd jack one rear wheel up in the air and then stick the gear box in 5th gear. You can then get someone to bump the engine round using the rear wheel whilst you watch the valves on cylinder number one, you can poke something down the plug hole which helps you feel for the piston.

Doing the above means that you can feel the piston going down whilst the inlet valve is open, then as the piston starts coming up the bore the valve should close, when the piston is nearly at the top start to look at the damper wheel timmg marks, when the piston is around 10 degrees BTDC stop turning the engine. This is around the point the the plug should fire. Take the cap off the dizzy, the rotor arm should be pointing where one of the HT posts in the cap was, this is HT post number one. Also if you look at the trigger wheel in the dizzy one of the spikes should be virtually in line with the centre of the pickup coil. (It should in fact be just past it).

If the spike and the pickup are not lined up twist the dizzy until they are. Note which HT post the rotor is pointing at and connect HT wire number 1 to it. Then follow round with the others clockwise. 18436572.

That shoudl at least get the engine fired up assuming that there is nothing else wrong!

Forgot to mention I'm using a new (well 2nd hand) Facet fuel pump which if I recall I bought off you sidecar(bod) It does seem to back off when it hits the right pressure, so I think(!) it isn't flooding the carbs.

Thanks for the step-by-step - I'll give it a go and let you know
Cheers!
TimN

timnutt wrote:Forgot to mention I'm using a new (well 2nd hand) Facet fuel pump which if I recall I bought off you sidecar(bod) It does seem to back off when it hits the right pressure, so I think(!) it isn't flooding the carbs.

Thanks for the step-by-step - I'll give it a go and let you know
Cheers!
TimN

I ran that Facet pump for ages, it won't flood your carb unless there is crap in the float valves in which case any pump will flood the carb!

Sounds like you have two plug leads swapped, and the timing out.

Chris.

Ehh simple one, leads are 180 out.

Check markings on the pulley, check rotor position and work from there with your leads.