Hot starting

[b_l_macleod]

I have a Marlin Roadster with a 1.7 O series engine.

It has a hot starting problem.

I can drive say 10 miles, park, come back to the car a few minutes later and it will not start. Plenty charge in the battery, the temperature gauge on normal.

Any ideas?

This problem has meant I very rarely drive the car - to the extent that my wife wants me to get rid of it.

[stevejgreen]

Re: Hot starting

That sounds like fuel problems at first read.
Have you got spark, and fuel when it won't start?

You can eliminate the electrics by buying a can of 'EasyStart'. Follow the instructions on the can. If it starts then you have a fuel issue, if not it's electrics.

If it is fuel, its a case of working from one end to the other checking that everything is OK. It could be that you have some sort of cavitation caused by high temperatures.
Is there fuel in the float chamber etc etc etc.

Good luck.

[mark_tinkler]

Re: Hot starting

Does it look like the carb is flooding? How long do you ussually need to wait until you can get it to start again?

Make sure the choke mechanism is not sticking open. My father had a triumph where the outer cable of the choke had a joint that would break open sometimes and leave the choke on.

Also worth making sure the ignition is in as good condition as possible. Check the ignition points for pitting, set correct gap. Check ignition timing. Make sure vaccuum advance pipe is not leaking anywhere. Clean inside and outside of distributor cap, outside of ignition coil and ceramic of the spark plugs. Also check spark plug gaps. With the engine running in the dark look for sparking from high tension leads.

If you have SU type carbs make sure you have some oil in the dashpots.

[lil_red_roadster]

Re: Hot starting

In addition to the above it's not a "waxstat" jetted SU carb is it? These enjoy a very poor reputation especially for hot-running issues and are often swapped to a "normal" type of jet.
The following diagram shows the difference in shape between the jets.
http://www.rimmerbros.co.uk/ImagePopUp.aspx?i=GRID005600

If you do have the waxtstat style you may want to think about changing it for a plain jet. It's a quick & cheap fix.

[b_caswell]

Re: Hot starting



I have come across this problem when the fuel pump would not pump on starting from hot. It was a defective cracked housing and it then had problems overcoming the vapour lock in the system. Anew pump sorted it.

[CABRIOBOB]

Re: Hot starting

Brian, It could be the fuel is evaporating with the manifold heat, check float level and intake flanges for air leaks.
Do not use Easy Start as this will waste your engine as its like a drug and it will always want it, you will be better off removing the air filter and pouring some petrol in to the carb.

[myrkross]

Re: Hot starting

The manual choke SU HIF44 had an anti-runon valve on the vans, we had heaps of bother with them at the council here. they had a timer relay, and the valve was switched on for a few seconds when the ignition was switched offf.
These caused bad starting and rough running ussualy on start from hot. that is the first place i would look the HIF44 s were the carbs from memory.

[john cole77]

Re: Hot starting

I had the same problem with my 1.3 marina many years ago. It took me ages to get to the bottom of it. Did all the timing and electrics associated with the ignition. I eventually took the top off the carb and discovered that the needle was spring loadedto push against the side of the jet and this over time had worn the hole to an oval. A new needle and jet where fitted and the problem was solved.
Very easy to check, undo 3 screws and lift off the suction chamber and piston.

[info11]

Re: Hot starting

Well... i've had this problem for a few weeks... on my triumph roadster 2.5lt straight 6, it's got twin HS6 SU's.

Weak mixture..... simple as that.... i did everything you could image to trace it... as soon as i made it a little bit richer it was/is perfect... i even weakened it again to see if the problem returned... and it did.
Try it.....

[b_caswell]

Re: Hot starting

Hi Keith that looks a very smart Mk1 and I have added the pic to the register. Any chance you could email me the reg and chassis number to complete the entry.Ben Caswell.

[info11]

Re: Hot starting

Hi Ben

I'll send you the chassis number asap, reg is Q620 FWD
I now think it's a wide body version, as i took measurements from the build manual that was kindly posted in another thread, of the dash.... 34.5" after cutting the dash out i found it was 6" short... would that be correct?
I'm going to paint the car in the near future so will send better pics then...

[b_caswell]

Re: Hot starting

Now ive had a closer look at the enlargement and your reg number I realise its a hybrid with the live axle. The Mk1 dash would have been smaller but not by that much. Does it really need repainting?

[info11]

Re: Hot starting

How can you tell, or rather what can you tell from the reg number?
The chassis number is i think from memory 2434 or something like that... will need to check.
Live axle ??? whats one of them ?
all i was told when i got it was that it had a marina 1.8 back axle rather than the 1.3 as having the 2500 lump in it, would have made it rev too high...
It does rev quite a bit, though the overdrive does work and make a difference
yes it certainly needs respraying... i've already started the prep... crap paint on it...lots of marks.
the dash is 40" across...

[b_caswell]

Re: Hot starting

Hi Keith, I had set up a card index for that reg number and chassis number (2)484 with a straight six. A Mk2 chassis with a straight 6 must be a hybrid. It wont fit into a Marina based chassis.

When I looked closer at the photo you can see the proportion of the wing width and the rear leaf spring just infront of the rear wheel.
A live axle is what your car has (ie from a Marina) as opposed to the fixed diff and drive shafts that a Mk1 car would have.(ie from a Triumph Vitesse)

Your car is the same as mine and yes the dash is 40" the Mk1 car has a different dash moulding that makes the actual wooden dash smaller. Ben

[b_l_macleod]

Re: Hot starting

Thanks, I check out all those suggestions over the next week or so.