View Full Version : Difficulty starting engine

12-04-2008, 09:03 AM
Just a general question. When my car first became operational
and everything was new or professionally rebuilt- the engine
would start instantly on the first turn of the key.

Now the engine getting near to 2000 miles, it is
getting more and more difficult to start. I have to crank
it and crank it and crank it and crank it before it will
fire up. Once fired up it runs just great.

Something is wearing out with use. But I have no idea
where to look- short of replacing the ignition system again.



12-04-2008, 09:47 AM
Dale.......are you talking hot start or cold start? And for each type, how much do you have or not have the accelerator pedal pushed down? Some cars start better with the foot off of the go pedal while others like the pedal slightly depressed. Or sometimes a pump or two before turning the key helps. My car was one way when I first got it, a different way after rebuilding the carbs and completely different with TBI.

Gee...you could start a thread on hot vs. cold starting.......pump or no pump.....pedal depressed or not......choke in or out. So many variables and I bet it varies from car to car.

12-04-2008, 10:49 AM
BobbyD- A cold start with choke pulled out.

Until recently, I could start my car standing outside
by the turning the key with the choke pulled out.

With a warm start- no choke was or is needed.

Now I have to sit in the car and crank and crank
with some gas pedal action- cold engine only.

The warn engine cranks right up.

I want to replace the wearing out part BEFORE I'm
sitting 50 miles from home and the cold engine won't start.




12-04-2008, 10:58 AM
Dale, have some one work the choke knob at the dash and you watch what's happenning at the carbs. Don't be turning the ignition key, just work the choke cable. It could be related to the linkage problem you are having...

12-04-2008, 11:14 AM
Sounds like fuel problem.. Hopefully not as severe as the last fuel problem you had... Go get a couple cans of Chevron Techron and pop them in the tank, or STP fuel stabilizer. Drive it for a couple of hours then see what happens.

12-04-2008, 12:09 PM
Probably just needs a new set of spark plugs
or maybe a new coil!


12-04-2008, 02:12 PM
I would bet that the choke cable has slipped at the hold down screw on the carbs.
Check to make sure that at full on choke that the high idle cams (the rotating plates that the cable screws onto) are opening the throttle plates on both carbs.

12-04-2008, 02:32 PM
What about the fact that a while ago he was running full choke all the time. Maybe at 80* he doesn't need choke?

12-04-2008, 02:41 PM
That would be my best guess too. {choke problem} Choke not operating properly.
Were it me, I would look to see if the choke linkage and mechanisms were in proper working order before anything else.

12-04-2008, 02:52 PM
Choke makes sense. Dale, you could always do like I did with my old John Deere model B farm tractor and park it on a hill then coast to start it! :savewave:

Seriously, it has been great reading how you are finally enjoying your car!! Way to go!!

12-04-2008, 03:52 PM
The choke cables, thingybob cam lobes all seem in working
order. Also I can smell the rich mixture.

I've never had a stuck open choke before, Don.
I had a very rich mixture that I leaned out with the
special long tool from TRF.

You are correct, I need the choke only at cold engine start.
My engine sits in the garage at 80*F.

I made a test- Standing beside the car, choke full pulled out,
the engine started on the 8th crank of the key and went into a
very, very rough idle. Then it smoothed out after ten seconds or so.

Maybe I better pull a spark plug to be sure.


12-04-2008, 03:54 PM
Sounds over choked to me. Dale- You DON"T have to pull it out all the way.

12-04-2008, 04:14 PM
You may find that since you've been driving the car (finally), that the valves may have seated, and become too tight.
My rebuild engine did that. At first it would start instantly, then gradually became harder to start.
When I checked my valve lash, three valves were too tight. Readjusted, and now it starts instantly again.
I, like others in the forum, revel in the love/hate relationship that you and your car enjoy!
At some point you'll become familiar enough to be able to diagnosis and fix these minor annoyances, and DRIVE the car with confidence: well with semi-confidence.
Happy driving, Emmett

12-04-2008, 05:15 PM
What is valve lash?
My engine has not been rebuilt since
we bought it three years ago.



12-04-2008, 06:00 PM
3 years, but how many miles? It's not the age; it's the mileage. I'm sure you've heard that before.

12-04-2008, 06:39 PM
What is valve lash?
Also known as valve clearance, it's the space between the tip of the rocker arm and the end of the valve stem, when the lifter is on the base circle of the cam (ie valve fully closed).

It's a normal maintenance adjustment, generally every 12,000 miles or so (check your handbook). But definitely a good thing to check if you have otherwise unexplained problems with mixture, idle, starting, etc.

Emmett, I hope your clearances continue to stay stable. But having them close up in just a few thousand miles may be a sign of valve seat recession. They normally shouldn't "bed in" enough to measure.

12-04-2008, 07:01 PM
I may be wrong but I don't believe we (or Dale) have any idea as what engine work was done, e.g. how fresh the valves are or in fact if anything was done to the cyl. head and valve train.

Dale: Can you confirm this?


12-04-2008, 08:29 PM
Have you tried starting without choke and as the engine turns, slowly pull out the choke to see if there is a sweet spot for the choke that the engine likes?

12-04-2008, 09:39 PM
Would you believe the buddy system as backup till it's resolved?

You can always give it a good push while in first gear and pop the
clutch, if you have to.....

You can:

Buy the guys in the bar a beer and ask them to push start ya.

Or, have Wendy with you and ask her to push you (no high heels, please, on
these rides.)

Or, park on a respectable downhill slope to roll it down to start;

or you can push Wendy and hope she doesn't freak out when it starts...
(car can be just a little jumpy off the line) and do it that way....

Outta other ideas. Anybody got one to add??

Brings to mind another story: While in Mexico, guys used to jack the rear
wheels off the ground and, using a piece of rope, wrap it around a rear
tire and pull it off quickly spinning the tire, time after time, till it
starts. Reminds me of an old Gibson tractor I still own...and it still
runs, by the way.....pull rope start.

12-04-2008, 10:39 PM
I don't think that it's more than a change of season and a feathering of the choke, provided that all adjustments are as they should be.

12-05-2008, 08:10 AM
I may be wrong but I don't believe we (or Dale) have any idea as what engine work was done, e.g. how fresh the valves are or in fact if anything was done to the cyl. head and valve train.

Dale: Can you confirm this?


<span style="color: #660000">Confirmed- zero ideas what might have been done to
the engine itself. I've had the valve cover off twice- once to find TDC and
another time to adjust the valves. If DPO Pedro didn't spend the cash for
an oil change in the 3 years he owned the car, I seriously doubt his junkyard
mechanic attempted any major engine work.

My car starts, that's not the issue here.
The issue is it used to start much more easily, like
on the first turn of the key. Paul is probably correct
with his weather theory. It is much cooler now.



12-05-2008, 10:05 AM
The more miles the engine runs, the greater the tendency for your valves to press in tighter in their seats. When this happens the valve stem begins to raise up higher, closing the small gap between the rocker arm and the top of the valve stem, effectively holding the valve slightly open.
This can cause piston pressure to escape though this slightly opened valve, and actually blow your gas mixture out of the carburator throat, making it hard to start. once started it may seem to run ok.
So valve lash is the adjustment of the small gap between the valve tip and the rocker arm, when the valve is fully closed.
Most people retorque their head bolts and readjust valves at some point after an engine rebuild.

12-05-2008, 11:51 AM
Thanks for the valve advice Emmett but I think I better
not go there just now. It scared me half to death adjusting the valves the first two times.

I'm not very mechanically adept and my valves seem
operational and don't make a bunch of clatter. I added
the bottle of recommended fuel treatment and drove the
car for an hour this morning.

I think for now, I'll just enjoy driving the car until
it's next breakdown event. Here's my plugs at 1620 miles without
a breakdown. They look fine to me - nice toasty tan.




12-05-2008, 12:06 PM
Just what the doctor ordered; a nice ride in the tropics, while the rest of us bundle up and wait for the "clipper"

12-05-2008, 01:20 PM
When something similar happened with my TR3 it turned out that the choke was not fully working. The mechanism had become stiff and although I thought I was pulling the choke all of the way out, it was in fact not pulling it all the way out at the carburettors. (Thanks to this forum for resolving that one for me.) Once you have pulled the knob fully out at the dashboard, check that the mechanism has moved its full travel at the carburettors. There may be a little adjustment required. (On my TR3 the jets were not pulling down as far as they should and all I was doing was increasing the idling speed.) So check that everything is happening as it should.
I would have thought that if you were giving it too much choke, then it may start and then falter, or it would flood and not start at all.
Good luck.

12-05-2008, 03:33 PM
Yup.... It sounds like a choke issue to me.

12-05-2008, 09:31 PM
Then take the hands away from the throat :nonono:

12-06-2008, 03:47 AM
When my 6 got hard to start I found the points had closed up to about .008. I regapped to .015 and all was well; easy to check.


12-06-2008, 08:48 PM
Hey Dale. Here's a good video on setting valve lash. It's a 4 cylinder MG, so much of it doesn't apply to a TR-6, but you can see the basics of adjusting the valves (setting valve lash).


12-10-2008, 09:47 PM
Watch that "standing outside and turning the key" business...

I was working on my (sadly long gone) tricarb AH3000. Had pulled into the level driveway in front of the closed garage. Popped the hood, fiddled around a bit, and decided I needed to start it. Stood outside the drivers door, turned the key and hit the starter, then watched amazed as the Healey dutifully fired right up and lunged through the wooden garage door before I could catch it and yank the key to off.

Yes, I had forgotten it was in gear.

Makes me wonder how many oldsters got squished hand cranking their model T's...

12-11-2008, 08:56 AM
about the same number that got squished by their tractors, I would imagine. There was a fatality around here a few years back by that very thing, went to start an antique tractor and it pinned him against the barn wall.

I wonder if Dale's issue here was the leaky booster vacuum line.

Edited to fix my @#$@ speeeling

12-11-2008, 09:46 AM
about the same number that got squished by their tractors, I would imagine. There was a fatality around here a few years back by that very thing, went to start an antique tractor and it pinned him against the barn wall.

I wonder if Dale's issue here was the leaky booster vacuum line.

Edited to fix my @#$@ speeeling

<span style="color: #990000">Nope Steve, slow start not corrected. I admit
I've done very little to fix it. (other priorities and some health
issues at the moment.

The car does start, after several cranks, and then
settles into a decent idle. It seems to lack a little get up
and go on the highway, so I'm thinking I could have messed up
the timing when I installed the new plug wires and dizzy cap.