• The Roadster Factory Recovery Fund - Friends, as you may have heard, The Roadster Factory, a respected British Car Parts business in PA, suffered a total loss in a fire on Christmas Day. Read about it, discuss or ask questions >> HERE. The Triumph Register of America is sponsoring a fund raiser to help TRF get back on their feet. If you can help, vist >> their GoFundMe page.
  • Hey there Guest!
    If you enjoy BCF and find our forum a useful resource, if you appreciate not having ads pop up all over the place and you want to ensure we can stay online - Please consider supporting with an "optional" low-cost annual subscription.
    **Upgrade Now**
    (PS: Subscribers don't see this UGLY banner)
Tips
Tips

TR6 Issue of the day......restart and idle after shut down

edkap2002

Senior Member
Country flag
Offline
Hello,

My recently purchased 72 TR6 has offered few surprises and disappointments....however one issue remains and Im not sure of the cause.

On cold start, full choke, starts right up but it takes a little while to get to high RPMs.....then it does and warms up fine. When warm....perfect idle 750 rpm.....I go out for a twenty minute drive and the car drives strong and great but i i shut it down, even for 5 minutes....I have to do some real cranking of the starter to get it running......and when it starts it no longer wants to hold that 750 rpm idle...more like 400 - 500.....my guess is the fuel is heading back towards the tank when not running......is this a fuel pump issue or a leak in the line symptom? any help would be appreciated.....Ed K
 

TR3driver

Great Pumpkin - R.I.P
Offline
Each carb stores a small amount of fuel in the float bowl, with what amounts to an air break between it and the fuel pump. Only way to lose that is to have a big leak, and even then it would be the same cold as hot.

So most likely you're having trouble with it going rich instead. To confirm, have someone watch the tailpipe during a hot start; they'll probably see black smoke.

One of the most common causes of that is heat from the exhaust manifold causing fuel to boil in the carbs. Here's a thread with some solutions https://www.britishcarforum.com/bcf/showthread.php?63423-Do-heat-shields-really-work

(Joe's web site seems to be down at the moment; he told me some time ago that it was being refurbished. But I'm fairly certain he's still in business; or you can buy his heat shield at a slightly higher price from most other TR6 vendors.)
 
OP
edkap2002

edkap2002

Senior Member
Country flag
Offline
Hi, thanks for responding...I agree with the rich theory...no black smoke whatsoever...there is a faint smell of gasoline where I store the car....does that add to the mystery?.....Ed
 

Tybalt

Jedi Warrior
Country flag
Offline
Is it any better when the tank is full over when it is low? What about behavior going uphill vs down hill? I have seen similar behavior due to a still working but not really up to the task fuel pump. If it behaves better when the tank is full or when going down hill (especially if there is any significant grade and length to the hill), it's likely fuel pump time.
 
OP
edkap2002

edkap2002

Senior Member
Country flag
Offline
I am thinking you are right about the fuel pump...it looks to be original. I will order one and get back after installation and thanks.
 

mrv8q

Luke Skywalker
Country flag
Offline
...Or just rebuild yours, if it’s an original pump.
 

mrv8q

Luke Skywalker
Country flag
Offline
The latest I got from TRF did not, if you are referring to the priming lever under the pump.
 

poolboy

Yoda
Country flag
Offline
No..that's not part of the kit..any DIY kit that I've ever seen.
But FWIW, it probably does not need replacing.
There's a picture in the TRF catalog of the parts included in their kit.
https://trf.zeni.net/wc/specials13.15/26.php


Those symptoms do sound like fuel percolation, however the 60 degree temp doesn't.
I never experienced percolation until the contributing factor of the ambient temperature was about 90*F and then only when the engine got good and hot.
At only 20 minutes, your oil was just getting to normal operating temperature.
 

wingler

Freshman Member
Offline
I will be interested in your resolution here, as I have the same issue with my 74 TR6. I have installed the heat shield from TRF, and my fuel pump is fairly new. My car starts fine, idles fine, and runs fine from a cold start. Also operating temperature is normal. However, after driving the car for a while, if I turn off the engine and try to restart within 15 or 20 minutes, temp gauge is it 3/4, car is hard to start, and runs rough, or cuts out. All goes back to normal, temperature, and engine performance, after driving for a few minutes.
 

poolboy

Yoda
Country flag
Offline
That sounds like fuel percolation. The heat shield alone didn't do much to cure the problem...but when I lined the floor of the heat shield (top and bottom) with a couple of layers of "heat insulation" that cured it.
https://www.jegs.com/i/Thermo-Tec/893/13575/10002/-1
TR6heatShield.jpg
 
OP
edkap2002

edkap2002

Senior Member
Country flag
Offline
I will be interested in your resolution here, as I have the same issue with my 74 TR6. I have installed the heat shield from TRF, and my fuel pump is fairly new. My car starts fine, idles fine, and runs fine from a cold start. Also operating temperature is normal. However, after driving the car for a while, if I turn off the engine and try to restart within 15 or 20 minutes, temp gauge is it 3/4, car is hard to start, and runs rough, or cuts out. All goes back to normal, temperature, and engine performance, after driving for a few minutes.

I will let you know for certain when I get is resolved...Im thinking about replacing the fuel lines all the way to the tank
 

CJD

Yoda
Country flag
Offline
Starting good cold, but not well hot could be a rich condition. Have you tried starting it cold with no choke? If it does start well cold with no choke, then you are running very rich for some reason. The first step then would be to lean out the idle mixture.

If it does not start well cold with no choke, then percolation would be the cause of the rich when sitting hot. The solution then would be to slightly lower the fuel float levels to keep the fuel in the bowls instead of running down the manifolds and accumulating in the intake.
 
OP
edkap2002

edkap2002

Senior Member
Country flag
Offline
Starting good cold, but not well hot could be a rich condition. Have you tried starting it cold with no choke? If it does start well cold with no choke, then you are running very rich for some reason. The first step then would be to lean out the idle mixture.

If it does not start well cold with no choke, then percolation would be the cause of the rich when sitting hot. The solution then would be to slightly lower the fuel float levels to keep the fuel in the bowls instead of running down the manifolds and accumulating in the intake.

John...sounds like great advice and I try the cold choke-less start as soon as I return home...thanks much....Ed
 
Similar threads
Thread starter Title Forum Replies Date
R TR2/3/3A Overheat issue, gauge adjustment Triumph 9
T 100 BN2 Possible Ignition Issue Austin Healey 7
B MGA Tach drive issue MG 1
K TR2/3/3A Turn signal flasher issue.....electrical is not my strong point. Triumph 13
J Issue with Reverse Spridgets 2
Celtic 77 MGB Seized air pump issue MG 25
H TR4/4A Advise asked on TR 4 a frame collision/issue Triumph 20
S TR2/3/3A Triumph TR3 Tail Light Issue when Headlights and Brakes are On Triumph 15
B General MG Turn Signal Issue MG 1
wkilleffer MGB 1974 MGB SU fuel pump voltage issue MG 11
K TR2/3/3A Brake issue? Triumph 8
M TR6 Alternator Issue for 72 TR6 Triumph 7
A TR6 TR6 Distributor cap issue Triumph 4
EricJNewman MGB Weird Brake issue finally solved. MG 1
B Any issue with cutting this weld on the spring base plates? Spridgets 4
Kolecki TR2/3/3A engine assembly cam timing issue Triumph 8
K TR2/3/3A Hot day coolant overflow issue.... Triumph 1
C TR2/3/3A Water pump issue Triumph 8
Guido36 Chassis Number Issue Austin Healey 11
Got_All_4 Wedge An issue with trying to start my TR7 Triumph 12
mch979 1967 MGB GT bonnet issue MG 25
H T-Series Brake Issue MG 5
K TR2/3/3A Steering Issue? Triumph 23
P TR3B Coil Issue? Triumph 7
Lin Excellent Issue of the Marque Magazine Austin Healey 2
R TR6 Is this a starter issue? Triumph 6
M Lighting issue Austin Healey 3
B TR4/4A Thrust washer issue Triumph 11
jfarris Honda Parts Issue? Other Cars 1
S TR6 TR6 Vacuum Issue... some help please... Triumph 8
M Heat-related carb issue on BN1 Austin Healey 7
M TR6 Starter lagging issue Triumph 2
M TR6 PDWA Issue Triumph 5
R Issue with odometer after repair Austin Healey 1
Michael Oritt Bulb holder issue Austin Healey 5
D TR4/4A rebound stop clearance issue Triumph 13
S BJ8 Overdrive Issue Austin Healey 7
Michael Oritt Brake issue Austin Healey 24
G MGB Starter and fuel issue MG 6
S BJ8 Overdrive issue Austin Healey 10
M Help with 60 Bugeye - major drivetrain issue... Spridgets 78
catfood Looking for suggestions - ignition issue Austin Healey 6
N Electrical issue. FORUM Navigation Questions 2
Lin Another trafficator issue Austin Healey 8
J TR2/3/3A Hastings Piston Ring End Gap Issue Triumph 16
glemon General Tech Turn Signal Issue Triumph 12
Michael Oritt Speedometer drive issue Austin Healey 4
H Post-War Other Wiper Motor [Early type DR2] Issue Triumph 7
S TR2/3/3A Electrical Issue Triumph 40
F TR6 Frame Issue Triumph 11

Similar threads

Top