1983 110 V8 starting oddity

parptoot · Oct 4, 2019

Hello all, You've aided me with an an overheating issue, which is all sorted now, so I would now like to ask about the starting process I have to go through. I hope it's a simple one.

It starts every time, I don't struggle to start it but it's not a straighforward process, well, i't just not normal.

If its properly cold, pull out the choke a couple of CMs
Turn on ignition, allow the pump to pump
5-6 full pumps on the throttle
It will then Start on the button
It will then stall a few seconds later if the revs are not kept up a little
Once past that, it's fine.

When it's stopped and started again in that running period, then it'll start again.
If left to sit for a while it will start but I'll have to do the pumping on the throttle agian.

My thought is that the fuel is falling back down the system and that early start will run on the fuel in the carb then stall as it waits for the fuel to come up from the pump, right?

The specs
1983 110 V8 County
Webber/Holly carb
Some sort of aftermarket fuel pump on the chassis under the drivers seat
The engine is tired and breathes a lot (it's due a rebuild)

Other than all that, it runs fine.
Does anyone have any ideas about that odd starting process? Fuel pump? One way valve? something else?

Thanks.

kermit_rr · Oct 4, 2019

When you're pumping the throttle, you're dumping fuel into the manifold.
My guess would be the choke needs adjustment to keep it running for the few seconds is cold
Could also be an air leak that means it's running lean at cold
What are the plugs like?

marjon · Oct 4, 2019

I would have to agree that shouldn’t be like that. Is it something that has always been like it or has it been a gradual process?
Personally I would be inclined towards.

A carb clean and rebuild, sounds like choke is not working properly or jets are blocked. If the pump is actually working it should prime/fill the carb in seconds.
Fuel filter?
Check for air leaks. Below carb.
Check all the ignition system.

When you pump your throttle you will be squirting fuel into the manifold, think that’s the design of the Weber and others, a little pump of gas when you floor it to help acceleration, mix/load.

All pretty simple things to check and do too.

Good luck.

J

parptoot · Oct 4, 2019

Aha, that makes sense! Dump fuel in to start it then it needs the revs holding up for a few seconds to stay running because it's a weak mixture.
Plugs are fine and were changed recently and made no difference to starting or running.

I've just remembered that the previous owner said they had to adjust the carb to pass the emmisions part of the M.O.T. I wonder if it wasn't readjusted back to where it runs better....hmmm.

marjon · Oct 4, 2019

parptoot said:
I've just remembered that the previous owner said they had to adjust the carb to pass the emmisions part of the M.O.T. I wonder if it wasn't readjusted back to where it runs better....hmmm.

Depends what they adjusted, but cold starting should have nothing to do with MOT emissions.
Emissions are tested at running temps.

What sort of carb model is it?

J

parptoot · Oct 4, 2019

I've had it for a year and it's always been the same. It's not particularly irritating, more of a quirk.

Ok, a possible job for a weekend once some bits are gathered. Or I go the lazy route and get it done for me

I have been toying with the idea of swapping over to that Holly/Webber fuel injecton carb thing. It looks easy and relatively foolproof, without losing the carb look. I will however be looking to get this sorted.

parptoot · Oct 4, 2019

marjon said:
Depends what they adjusted, but cold starting should have nothing to do with MOT emissions.
Emissions are tested at running temps.

What sort of carb model is it?

J

I think it's the holly 500? I have a manual somewhere.

parptoot · Oct 4, 2019

marjon · Oct 4, 2019

parptoot said:
Ok, a possible job for a weekend once some bits are gathered. Or I go the lazy route and get it done for me

Easy relaxing weekend job sat at a bench

Only really a few gaskets and manual required, then setting up after, can been done with a bit of “ear” and trial & error

very satisfying job too.

Getting somebody else to do it,

you’ll be lucky these days. You need the “ole boy” in the corner of an old garage

these days.

J

parptoot · Oct 4, 2019

marjon said:
You need the “ole boy” in the corner of an old

Shame isn't it. All those skills are going to disappear.

marjon · Oct 4, 2019

parptoot said:
Shame isn't it. All those skills are going to disappear.

Afraid to say it but yes.
I wouldn’t even try to get my bike in and have all 4 carbs setup/balanced.

But it’s not difficult.

J

Shippers · Oct 4, 2019

In the time that you have the pump running before cranking the engine to fire up if you put a piece of clear pipe on the return to tank you'll see if there's air in the system indicating a leak somewhere...if you don't pump pedal will it still start?

kermit_rr · Oct 4, 2019

Is it a manual or automatic choke? On some carbs an auto choke is engaged by pressing the accelerator pedal.
Check the action of the choke and that is working properly

kermit_rr · Oct 4, 2019

marjon said:
Easy relaxing weekend job sat at a bench

Only really a few gaskets and manual required, then setting up after, can been done with a bit of “ear” and trial & error very satisfying job too.

Getting somebody else to do it, you’ll be lucky these days. You need the “ole boy” in the corner of an old garage these days.

J

I'm not what you would call old, but carbs are definitely my thing, bike or car

Shippers · Oct 4, 2019

kermit_rr said:
Check the action of the choke and that is working properly

Yes my 101 the PO had connected the hand throttle for the winch to the choke and the vice-versa..when I rebuilt it with all new cables I just copied what was there... had real starting problems till I looked at repair manual one night and thought mine doesn't look like that... so after numerous strip down and non return valves a cable swop sorted it...

parptoot · Oct 5, 2019

Shippers said:
if you don't pump pedal will it still start?

From memory yes, however it take a lot more turning over.

kermit_rr said:
Is it a manual or automatic choke?

Manual.

hef19898 · Oct 29, 2019

Interesting thread, the start behaviour sounds a lot like mine, doesn't like humidity. Still starts every time without much trouble. I'll definitely follow that!

parptoot · Oct 29, 2019

hef19898 said:
Interesting thread, the start behaviour sounds a lot like mine, doesn't like humidity. Still starts every time without much trouble. I'll definitely follow that!

It's only mildly annoying really and I've just got used to it. Come the big rebuild, it'll be looked into more closely and rectified once and for all.
It's a bloody awful way to get to work and back really but I think it's great.
"Aren't you cold?" Yes but I can wear gloves
"You smell of oil and petrol" Yes but I enjoyed my drive to work, how about you in your Euro-****-box?
"It's very big, is it easy to move about" Yes, I use these orbital attachments on the front of my face to look where I'm fecking going

1983 110 V8 starting oddity

parptoot

Well-Known Member

kermit_rr

Very

marjon

Well-Known Member

parptoot

Well-Known Member

marjon

Well-Known Member

parptoot

Well-Known Member

parptoot

Well-Known Member

parptoot

Well-Known Member

marjon

Well-Known Member

parptoot

Well-Known Member

marjon

Well-Known Member

Shippers

Well-Known Member

kermit_rr

Very

kermit_rr

Very

Shippers

Well-Known Member

parptoot

Well-Known Member

hef19898

Well-Known Member

parptoot

Well-Known Member

Similar threads