TR3 rough running

[EliTR6]

Hi all, not my car but someone nearby asked me for help with his 3.

Petrol is getting to the carbs OK but was very difficult to start. 

Took the plugs out, very wet and fouled. Cleaned and gapped, started better and idled nicely but misses a lot under acceleration. It's pretty much undrivable and the owner is at a loss what to do. 

Can someone please confirm that these are h6 carbs? There was no tag on the float bowls. 

There's a stray wire coming from the distributor body. Leftover from an earlier electronic ignition setup? 

I had to call it a day but next step is to fit new points and condenser, try a different coil and swap plug leads. 

I'm fairly certain the problem lies with the carbs so I'll check that the pistons drop OK without sticking and start afresh with baseline settings (2 full turns from level with bridge?) if the jets don't need centering. 

Bonus question: he's got these gorgeous mesh headlamp guards. Anyone know where he could source a knurled nut like the one in the photo? Merc! 

 

[RobH]

Those look like H6 carbs all right.  What float valves does it have?  I had Groze jets and had similar trouble because they didn't seal properly, so the carbs were flooding intermittently.  The original style viton tip needles work for me but those can flood too if they are worn. 

 

Edited July 7, 2022 by RobH

[Hamish]

Is that wire with the fork to a condensor ?

certainly look like the longer h6

is there oil in the dash pots?

[BlueTR3A-5EKT]

Yes H6

The black wire with forked end connector going to a condenser is a left over from attempted ignition noise suppression to stop crackle on the car radio ( if fitted)

The knurled thumb nut.  You might ask Moss if they have any warranty stoneguuards that you could buy the nut from.  But I suspect they only sell clip on type now.    Failing that given a drawing with thread size and type I could probably make in stainless steel.  Not a cheap option I fear. 

[Lebro]

Is ignition timing correct ?

Bob

[Hamish]

Eli

they may be metric but could sort your mate out at a reasonable cost

thumb screws

https://www.ebay.co.uk/itm/164838535376?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=69jnVP1HQY2&sssrc=2349624&ssuid=33-Tg7STSaq&var=464326130164&widget_ver=artemis&media=COPY

 

search stainless thumb screw and you have a choice 

Edited July 8, 2022 by Hamish

[TR4TUNE]

If the car has not been used for a while and/or the choke has been used to aid starting then check that the jet is not sticking open when the choke is released.This happened to one of my H6 carbs after lack of use over winter, jet stuck down leading to very lumpy running and wet plugs. I try to remember to open and close the choke every week to prevent the jet sticking to the cork seals.Cue discussion on viton/teflon vs cork seals........

[stuart]

When was the last time he put fresh fuel in it?

Stuart.

[EliTR6]

Thanks everyone. I'm going away for a fortnight but have another go when I'm back. 

There aren't really any good garages nearby and the owner isn't really at ease doing the work himself so it's only been driven up and down the road a few times in the past couple of years. 

The fuel is more than a year old, I asked him to put fresh petrol in next time. I'll check static timing and bring my timing gun with me to make sure the advance is working OK. 

It's a pricier and time consuming solution but I think it's worth rebuilding the carbs (ourselves) and checking the floats are OK so he can enjoy the car without worrying.