Random stalling - not sure why...

Carbs; K-jet; Tanks; Lines; Filler necks, Senders; aftermarket fuel systems; Exhausts and Manifolds;air filters - standard and aftermarket
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Johnny_E
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Random stalling - not sure why...

Post by Johnny_E »

OK. I'm not sure where this problem lies - so I'll just tell you the running order and we'll see...

I was driving back home a few days ago - fuel needle was at the top of the red. I'm not used to the car, so I assumed that was fine. Suddenly, the car started to stammer. 5 secs later - dead. Managed to freewheel to a layby and call the missus. Assuming a sticky float in the tank (ie. I'd run out) - I stuck 5l in and away we went. I must say at this point that once it conked out I didnt try more than once to restart the car until I'd got more juice. It'd cooled down considerably by the time I filled it with the can.

So - last night - took it for a quick pre MOT run. 1/2 a mile up the road... stammered and conked out. It literally dies in 5 secs. Pulled over. Wouldnt fire (cranks OK). 2 mins later - fired up fine and home we went.

So - assuming that 5l aint enough - I stuck £20 in.

This morning was MOT day (nerves killin me!). 4 miles from home.... stammer and conk. Tried and tried to start it - wouldnt fire. Sat 5 mins... fired fine. Made it 6 miles.. same again.

Got to the MOT centre and with heart in throat went through... (NI - has a govt run test centre - you have 1 shot at it on the rollers for brake bias tests etc etc). The car passed with flying colours I'm glad to say. :hugegrin:

Made it 5 miles without issue to work.

Coming home this afternoon - same conking issue - 3 times :dash:

So - fault finding time: 1 thing I'm wondering... did I run out of fuel at all on Tuesday? I'm doubting that now. Its behaving the very same with £20 in the tank. However, if it DID run out, maybe theres crud in the lines. But that wouldnt explain it conking - and starting fine 3 mins later. The crud wouldnt just disappear.

Someone suggested it could be the coil on the way out. Its in a really crap place IMO - with all that heat round it. I looked at the fuel line to the carb tonight as it ticked over in the drive. Theres a wee inline Fram filter near the carb - and theres no crud in there. However, at tick over - theres LOTS of air bubbles travelling in the line. Is that normal?

I'm stumped - and quite pi**ed off. This is the last hurdle to getting this wee Cat D back to top form.

Any ideas? :beg:


Nate
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Re: Random stalling - not sure why...

Post by Nate »

when it dies, soes it feel like it's running out of fuel? think this one is going to need the tank opening - blocked pickup and our old favourite the rusty filler neck methinks


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Johnny_E
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Re: Random stalling - not sure why...

Post by Johnny_E »

Yup. It stammers, loses power, picks up.... then cuts out. Sit at the side of the road for 5 mins and all is well again. Tell me the pickup is easy got at! Last time I had tank trouble was on my TR7v8. Back axle out job.


Nate
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Re: Random stalling - not sure why...

Post by Nate »

take the bottom of the rear seatr out. remove inspection cover (3 screws) then unscrew sender from tank. check the pickup isn't clogged with rust. if it is, chuck a magnet in the tank, fit a new fuel filter and open up the holes in the pickup. then check your filler neck for rust


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Johnny_E
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Re: Random stalling - not sure why...

Post by Johnny_E »

Nate wrote:take the bottom of the rear seatr out. remove inspection cover (3 screws) then unscrew sender from tank. check the pickup isn't clogged with rust. if it is, chuck a magnet in the tank, fit a new fuel filter and open up the holes in the pickup. then check your filler neck for rust
Dead on. I've had a look at the pics in the Haynes. Thank frig the rocco is FWD. I had month of work with the old TR - which had a shot tank.

1 question - should I buy in anew sealing ring/gasket? If so, wheres the best place to get one?


Nate
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Re: Random stalling - not sure why...

Post by Nate »

it wouldn't hurt, but i never have in the past. obviously if it is perished then it'll need one. try your local dealer


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Johnny_E
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Re: Random stalling - not sure why...

Post by Johnny_E »

OK.. had a look just now. One thing I'll thanks the Germans for - it an easy to get at fuel sender. A total contrast to the daft TR7 setup.

Popped off the back seat base, took off the 2 fuel pipes and with a rubber mallet, knocked off the sender/pickup. Took it out and inspected it. There was little or no crap in the pickup. Just maybe 1 or 2 holes clogged. Looked into the tank, and its not too bad. There were however some fragments of rust swimming about - in the region of the pickup.

So, I popped 3 very strong magnets in there and blew out the pickup (thank frig fro Aquafresh mouthwash :hugegrin: gets rid of the petrol taste every time)

Then, I had a closer look at the inline fuel filter and decided this time to take it off. It hadnt looked TOO bad visually - so I removed it and gave it a few taps with a screwdriver. :shock: Wow. A lot of crud appeared from the paper filter fins. Sorry for the crap phone pic - but I think despite it being out of focus, you get the picture:

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So, whaddya think? Enough crap to cause fuel starvation on load? I think so, but then I'm a not exactly an expert.

Oh... and is this it for filters? Is there one anywhere else or if this the one and only filter to be checked?


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Funky Diver
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Re: Random stalling - not sure why...

Post by Funky Diver »

Could well be that there's MUCH bigger bits of crud in your tank blocking the pipework at that point.

Get your tank cleaned out, chuck a coupla magnets in and check your filler neck, replace neck, replace filter then replace again after running for a while.


Nate
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Re: Random stalling - not sure why...

Post by Nate »

it could also be down to a bit of water getting in if it is your filler neck gone. once a new one fitted, run some wynn's dryfuel thru it to get rid of anything that's left


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Johnny_E
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Re: Random stalling - not sure why...

Post by Johnny_E »

Well, I took a decent look in with a torch - and there were literally just about a dozen tiny fragments left in the tank - about 1mm in size. I had 3 very strong magnets that I've chucked in - and I used a long screwdriver to pull the fragments over to them - and they stuck instantly to them.

I'll pop a new filter in and see if any more gets sucked through the lines, then as you say get a 2nd filter put on.

A new filler neck is on the cards for sure long term.


Johnny_E
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Re: Random stalling - not sure why...

Post by Johnny_E »

Nate wrote:it could also be down to a bit of water getting in if it is your filler neck gone. once a new one fitted, run some wynn's dryfuel thru it to get rid of anything that's left
Good idea - I'll get some Wynns. My brother in law has what I can best describe as a big bendy stick with a magnet on the end - so I'm going to sweep the tank base with that tonight to clear any debris.

Thanks for all the tips chaps.


philiano
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Re: Random stalling - not sure why...

Post by philiano »

did you manage to find the cause of the problem?
We're having the same problems with our Golf Clipper, and I'm gonna take a look at the tank fuel pickup tomorrow.
I'm thinking of changing the fuel pump too, see if it makes any difference.


steve
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Re: Random stalling - not sure why...

Post by steve »

If you've got a carb - could be icing? There's a lot of it about at the minute.


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Johnny_E
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Re: Random stalling - not sure why...

Post by Johnny_E »

philiano wrote:did you manage to find the cause of the problem?
We're having the same problems with our Golf Clipper, and I'm gonna take a look at the tank fuel pickup tomorrow.
I'm thinking of changing the fuel pump too, see if it makes any difference.
In my case it was a dirty inline fuel filter. It was a fram filter, inline just before the carb. It looked fine but when removed and tapped, it was sludged up.

Also opened up the tank, but all was well in there.


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whiteshark
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Re: Random stalling - not sure why...

Post by whiteshark »

Johnny, where are you based?


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