maybe carb fault

[ogdenenterprise]

I mentioned this week that I tried to start my Haf but found it was out of fuel. I have filled the tank, then found the battery dead, so I replaced the battery and it now cranks but does not start. I have stripped and cleaned the carb which is a zenith 32 ndix, the plunger was in good condition and all the jets seemed clean. I put the fuel pipe into a container and cranked the engine and it seems to be pumping fuel ok, its the original type engine pump. I have put it all back together but still no joy. I seem to remember that when you pumped the accelerator lever on the right hand side, as you looked in the top of the carb you could see fuel squrting from the two small brass tubes that point down the throat of the carb, at the moment there is nothing showing. I also removed one of the plugs and it was dry but I didnt check for a spark, but I seem to think it is a carb problem. Has any one any suggestions?

Dave

[AustHaflinger]

Put a squirt or two of starting fluid (Aerostart or Start ya Bastard) down the carb throat and try starting - if it fires and runs all it needed was a bit more cranking, if it fires but does not run, the electrics are most likely OK but there is a fuel issue, if it does not fire then electrics are a possible cause.

If you move the accelerator pump you should see a little fuel squirting into the throttle body when viewed from the top of the carb.

Garry

[heinkeljb]

If it has been standing for a while it is possible the pump diaphragm is a little bit stiff - also Dynastart cranking speed might not be enough to actually pump fuel at the rate required.
Try Gary’s suggestion and hopefully with reasonable engine speed it will make the pump work correctly.

John

[calicobramble]

Good morning, been lurking for a bit but this shut down gives me the chance to isolate in my shed with a Haflinger to mend.

I've fitted an electric pump, but I'm concerned about the closed valve pressure on these as the float valve seems to only want very low pressure supplied to it, otherwise it gets swamped. Does anyone have any experience of sourcing a pump with a low enough closed valve pressure, only this doesn't seem to be a specification that is easily available for what I see on the 'net.

Best rgds Simon

[AustHaflinger]

Hi Simon and welcome to the forum - I am assuming you are in the UK. Please add your town, county and country to your profile.

I have always used electric fuel pumps - see this recent thread on the subject where I outline what I have fitted.

http://thehaflinger.com/viewtopic.php?f=23&t=3746

Garry

[heinkeljb]

Try this one:- Facet Posi-Flow Fuel Pump Single Carb 60104 Low Pressure 1.5 To 4.0 Psi ADV

Put that as your search in EBay and it should give you a resonably priced pump

John

[calicobramble]

Thank you John, I like those Facet pumps and have ordered the very same.

I bought one which said it was Facet in the advert but when it came it didn't have the name on the pump, only on the package. The advert is vague about what pressure it develops, and was half the price of the one I've just ordered. Same old same old, buy cheap buy twice.

Hopefully the genuine article turns up soon. I've got another on a diesel tractor and it works a treat.

Thanks for your help

Simon

[ogdenenterprise]

I tried the start ya bastard method but there was nothing. I then checked the points and yes there was a spark, but a weak one so I cleaned the faces up so I got a good spark. I then put a meter on both plug leads to check continuity from the cap to the spark plug, one of the faces on the distributor cap was a bit intermitant so I cleaned them as well. I put everything back together and nothing. so pulled the distributor cap off again, It has the nut type terminals on the coil, cap & plugs so it takes a bit longer to do. I had a spare distributor arm so I changed that, put it all back together again, and it tried to start, it was coughing and back firing till eventually it started to run smoothly. I left it running for about 1 hour after that. I was convinced it was the carb but I was proved wrong. I just hope it starts the next time I try it.

Dave

[AustHaflinger]

Yep "Start ya Bastard" - and yes for the Brits it is the brand name - helps sort whether issues are ignition or fuel.

Garry

[heinkeljb]

Backfire's are usually a sign of an air leak some where. Usually on the exhaust and usually when it is hot and on overrun. Coughing and backfiring on startup suggests ignition timing and possible bad valve tappet gaps, producing a slight leak on a valve seal. Do you have a compression tester? If yes, try sticking that on and see. If no, then at least check the valve gaps.

John

[ogdenenterprise]

I tried starting it again today, It started straight away and ticked over perfectly. I think this must have been a problem since I rebuilt the Haf. I dont start it often and i have always had problems with one or the other plug fouling so fingers crossed that has been the problem. The distributor finger was replaced at the same time as the rebuild.

Dave