19 replies to this topic

[mintyminis]

hello all

I had an unusual problem with the car about a mile from home, the car has been running sweet for sometime until tonight, I was going around a roundabout and as I accelerate the car would not rev up but cut out, the engine was warm and tried to start the car and started but as soon I touch the accelerator it cut out again, tried starting it again and it fired up ok but wont tick over and cuts out, and after a few tried it still wont run, I managed to get it running by keeping the choke fully on  but as soon I touch the accelerator with the choke out it cuts out again, so I manage to drive on just on choke without touching the accelerator. its a 1275cc with hif44 carb and electronic ignition, I tried to look back on old posts to see if anyone experience this problem but cant find anything yet. is there anyone that can give me an idea what could possible be the problem as need to get it fix as soon I can

many thanks

[sledgehammer]

a few quick things -

 

check dash pot has oil in (wouldn't usually cause a sudden problem - but you never know)

 

check fuel flow to the jet tube (as the choke would be enriching the mix to compensate)

 

take the fuel cap off - quick check to check fuel vent on tank

 

do you have a filter ? check it's clear & flowing thru

 

if not a fuel problem (choke gives slightly higher revs so may mask a electrical problem)

 

run engine at idle in the dark - look for sparks on engine acceleration

 

check all electrics ie cap is dry & clean - leads are good , coil nose is clean & LT is all tight

 

cleverer people will be along soon ...

Edited by sledgehammer, 30 March 2014 - 09:25 PM.

[dklawson]

Clever people have already posted Sledgehammer !  There is very little to add to what you have already suggested.

 

MintyMinis, how comfortable are you with checking the items above?  Post back for guidance on anything you are uncertain about.  

Edited by dklawson, 30 March 2014 - 10:03 PM.

[mintyminis]

thanks for the quick reply, I will go through that list of checks and will let you know if I get it sorted

[mintyminis]

ok, i tried going through the quick check list tonight, these are what i checked out... fuel flowing to carb ok... dash pot as oil as i can feel resistant when pushing cap in... no sparks under bonnet in the dark...all leads  connections are good...i have found another post which someone had the same problems as i'm having and turned out he has a blown exhaust and inlet manifold gasket which saying he had a bad air leak,.i have done all the checks for air leaks by spraying brake cleaner around the gaskets on the carb and inlet manifold..made no different to the engine while running while i sprayed,..i checked all breather hoses and pipes and no holes or worn..i have a servo which i cant check at the moment as i have not  got another small banjo nut to replace the one on the inlet to disconnect the servo and to try it and see if it makes any different ... what i have notice there is a slight play on the throttle spindle as if i grab hold of each end there is a slight rock in it, should it rock at all? also could it be dirt in the carb like a blocked needle? how easy is that to check? does the carb need to come off the inlet manifold to do these checks?

thanks

[cal844]

You say there is play in the throttle spindle, you need to get the spindle bushes changed, id imagine a machine shop could do this for you?!

I suppose you could remove the carb, strip and clean with petrol/ carb cleaner

[dklawson]

The play in the throttle shaft spindles will affect your ability to adjust the idle speed and mixture but it won't explain the engine dieing on you.  When an engine is turning over faster than idle, so much air passes through the carb that the leakage around the throttle spindle becomes negligible.

 

Does your car have a tach?  If so start the engine and watch the tach as you try to rev the engine.  If the needle bounces and drops when the engine dies, this indicates a problem with the low tension side of the ignition system.  If the tach slowly drops as the engine stops, this indicates a possible fuel problem.

 

You asked about checking for blocked fuel flow.  Which carb do you have on your engine? 

[mintyminis]

Thanks for repling, I will look at the tech tonight and let you know what it does,, it got a hif44 carb,

[mintyminis]

Hello
I checked the tech and it doesn't bounce so I guess it more likey a fuel problem with the carb? Is it a simple job to look inside the carb while still bolted to the engine or take it off and strip it apart which I want to avoided as I will have to get it tune up again? Thanks

[dklawson]

Start with the things you can check without pulling the carb.

 

First of all, you said it was hard to start and would only run with the choke pulled fully out.  Tip a thimble of gasoline down the carb throat and try to start the engine.  If it fires up easily and quickly dies, that would suggest fuel problems, not electrical/ignition.

 

Assuming this is fuel related, don't remove the carb as your first step.  Instead disconnect the fuel supply line from the carb and aim it in a catch jar.  Have a friend turn the engine over on the starter while you monitor the flow of gas into the jar.  If little to no fuel is flowing, look for filters and kinked lines between the tank and carbs.  Replace filters and fix the kinks.  Repeat your test to confirm fuel flow is restored.  If the flow is no better, make sure the fuel tank vent is not blocked.  Finally, try "sucking" fuel through the line.  If you can suck fuel through but the pump is not pumping it through, consider replacing the pump.

 

If you have good fuel flow from the pump but the problem persists... then it would be time to pull the carb.  While I have worked on a few HIF carbs I rather hope that others can tell you the quickest way to clean and sort them without touching the mixture adjustment. 

[mintyminis]

 ok I done some of the checks tonight, tank vent is not block, got petrol pumping into the carb ok, I got some carb cleaner so I decided

to take just the dashpot off to see if its dirty, as I taken the dashpot off, the piston and jet needle came out together so I taken them apart

and there was a fair bit gunge inside the piston so I gave them a clean with carb cleaner, also where the jet needle goes into a guide

in the main body I gave the guide a couple of squirt before I put everything back together ,once I put it all back I started the car with choke

on then tried the accelerator and it revs up!!..it now runs and smoothly while I rev the engine on and off..i let it warm up abit and took the choke

off and now it will tick over smoothly! so far it good news , the car now been running for 5min and no problems at all so I thought that's it,

car is now ok so I took it for  a test drive, got a couple hundred yards down the road,,,, it cut out again!  same as before, cuts out as I tried to rev up

 and only run on choke without using the accelerator so i'm back to square one again.. got the car back home,, hopefully someone could have a

good idea now what the problem is? 

[mintyminis]

Anyone got any ideas I could try as I got a whole weekend to try and fix the car. Thanks

[dklawson]

You made such good progress with cleaning the carb parts you could access that my suggestion would be to "bite the bullet" and carry out a complete carb rebuild off the car.  In addition to the deposits you found and addressed, there are likely more in the nooks and crannies.  It could still be a blocked or partially blocked float valve also which on an HIF carb is only accessible on the bench.

 

Hang in there.  You've made a lot of progress over the past couple of days.

[mintyminis]

Ok then,, going to take the carb off and give it a good clean, I will order some gasket kit first so I got everything I need to take it apart and clean then put it back together the same day.. Hope the problem does comes from the carb as need to get back on the road. Thanks for your replies, hope I sort it during the week and let you know

[dklawson]

Before you take the carb apart, read through the rebuild instructions in your service manual and also check online at the Burlen web site to see their technical guides on carb rebuilding and adjustment.  It will be very important for you to understand some of what is involved before you take things apart and equally important to know the "start from cold" settings needed to get the engine going before you tune the mixture.

 

Keep us posted with your progress.