GT6 Idle the stall - 60 seconds to re-start ?

[dellyend1]

Dear All, 

 

Been a while since on the forum as I've had the GT6 running fine and have just been enjoying the summer !  

Today though, car was taken for a spirited 45 min drive and when I pulled back onto the drive way , car gradually reduced revs from 800 ish down to 500 ish and then stalled. Tried an immediate re-start and starter motor sounded like not enough electrical juice as a very slow turn over , so stopped and waited for 1 min and then tried again. Car fired up and idled perfectly as if nothing had happened ? Apologies as this may well be an electrical fault and I have posted on the fuel system page, but my initially thinking that it is not electrical engine heat issues as the car re-started and ran fine after 1 min, so not enough time for engine to cool down ? I'm thinking vapor lock type issue ? 

Car is running SU HS6 carbs and standard mechanical fuel pump and have carb shields. 

Could I ask if anyone else as experienced or heard of this type of problem and if a vapor lock is a suspect how have people insulated their fuel lines ? Especially the metal T Section that branches to allow the second carb to be fueled ?

 

Many Thanks in advance

 

Jeremy

[Anglefire]

I would guess vapour lock - but the slow starter is a bit odd. I guess you didn't try to turn the engine by hand to see if it had stiffened up? 

Funnily mine was a bit of a sod to start after a short shut off today - but I do think its running a little lean as it also slightly pops and bangs on the overrun every now and then. I did adjust the one float level after I smelt petrol on startup but found that in the end to be the hose clamp not quite tight enough - but not before I'd made the float tweek. Then it wouldn't start and run with out a lot of choke - but then found I'd forgotton to plug the breather hose back into the carb. 

Fuel lines are not insulated - just a stainless heat sheild. 

[Pete Lewis]

just has the sound of being too rich   

try leaning it a bit  cant advise much of a tech answer as HS6 is not a std spec

and guess you have pancakes filters so high under bonnet heat really upset idle mixtures 

 

Pete

[Iain T]

3 hours ago, dellyend1 said:

Today though, car was taken for a spirited 45 min drive

Was the engine hot? What did the temp gauge say? It is odd it struggled to crank. 

[Don R]

Could be electrical? Just finished mine after 5 year rebuild, and after a run through town with fan cutting in and out the tickover started dropping.  Got home and tried to restart it and it was dead.  The alternator seems to out out enough to make the voltmeter move but when you put load on it there is nothing left- electrical boffin friend said the old alternator diodes deteriorate over time, mines now 12 years old (with the lay-up).

[Pete Lewis]

lack of use kills battery life they just decide to have no capacity at the most awkward times without warning 

take it to most battery sales have a programmed tester  thats not just set to make a sale but cycles the battery loads to prove its fit or dying 

do as said look at bad earths  check things like choke and speedo cables are not hot taking the earth loads 

and dead field windings will give the effect of a slow crank that builds ,a bit like having a flat battery

Pete

 

[dellyend1]

Many thanks all.

engine was not overly hot , temp gauge sitting at 2/3rds. 
 

something I did notice before idle stall was that red light (alternator / voltage ) did come on when at idle in traffic . Would this suggest a dodgy alternator and if so , (please excuse my ignorance) but would this contribute to a lowering of revs abs cut out. 
 

I’ll investigate the battery as well, it seems to charge ok on the CTec charger but have not checked if it is drained after a run . 
 

many thanks

 

jeremy

[Anglefire]

Red light means its not charging the battery - so chances are it was only just charging it when running. Depending on how the alternator is failing it is possible it could drop the revs. 

[Pete Lewis]

if the idle drops due to poor setting then quite possible its just dropped below the cut in revs needed to keep it charging  

unlikely to be the alternators problem  its you slow lumpy idle you need to get smoothed 

too far advance will stall or kick back the starter 

Pete

[Iain T]

17 minutes ago, dellyend1 said:

something I did notice before idle stall was that red light (alternator / voltage ) did come on when at idle in traffic .

I had two new alternators fail so I splashed out and bought a Brise. 

Iain 

[NonMember]

1 hour ago, Pete Lewis said:

too far advance will stall or kick back the starter

Yep, get that a lot. Sticky mechanical advance in the distributor can mean it starts perfectly fine most of the time but stalls the starter at every TDC when cranking straight after a hot stall.