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Wedge TR7 won't start -- arrggh

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sammyb

Luke Skywalker
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So I took the carbs off, replaced the torn mounts and put them back on the car (which took me three farging weeks -- in between writing, during daughters' naps etc...)

I went out to fire her up after tightening the last bolt and the battery was dead. Took the battery out my '69 Vette...

And it cranks, will even start on starter fluid, but won't fire on its own. I'm thinking we have a fuel delivery issue. I hope I didn't bend and crimp a fuel line or something...or maybe I have crap in the line. Hopefully my fuel pump didn't freeze up.
 
Ahh, the joys of LBC ownership. Do we own them or they us? I'm sure your right about the problem being fuel delivery, but can't come up with anything related to your having the carbs off. I suppose it has to do with getting fuel to the carbs as opposed to the carbs themselves. I base this on them being empty now where they had fuel in them before they were removed. The fuel pump may not have enough "suck" at cranking speeds, but after the engine's running it will keep up. Just a few thoughts. Don't despair, Good Luck and let us know what you find out.
 
It should have a full tank, and I was checking at the lines, and the line to the front carb at least had fuel drip out of it. I didn't have time to go through the complete look and see (like disconnecting the lines and cranking it to see if fuel was pushing.)
 
Sam, maybe in the process of removing the carbs, they got turned in such a manner that the needle valves are stuck shut, maybe due to evaporation of residual fuel?
I'm just grabbing at straws, here.
Although, when you get it running, I'll tell you an amusing story about a TR4A I used to have.
Jeff
 
Not grabbing at straws there Bugeye. Depending how long you had them off, Sam, that does happen. When I changed engine in my 7 last year, I had the carbs off for about a month. The fuel in the floats evaporated, creating a glue like substance stopping the needle movement, and plugging everything up. A good bath of carb cleaner and steel wool did the job.
Good luck
Paul
 
Myabe the 7 realizes it is the ugly duckling of the TRs and it can never compete with your 3 so it just trying to die slowly.
 
[ QUOTE ]
Myabe the 7 realizes it is the ugly duckling of the TRs and it can never compete with your 3 so it just trying to die slowly.

[/ QUOTE ]

That's not very nice /ubbthreads/images/graemlins/hammer.gif
 
So you're telling me I should pull 'em off again? (ARRRGGHHH)

They were off about a month.

Should I just spray carb cleaner in them, or dismantle the whole thing?

Whatcha think?
 
I just pulled out the piston, needle assembly, and sprayed good carb cleaner into the bowl through the hole. Then steel wooled and used a silver polish to make like new. I was lucky and didn't have to remove the bowls. Seemed to disolve all the crud. Never had the problem with the fuel supply again. Other things, yes, but not that.

Paul
 
I've had this happen too, but never on both carbs at the same time. I would check the easy stuff that effects both carbs... test fuel pump, blow into fuel line from tank to confirm no blockage, etc.

I always keep an electric fuel pump in the boot to get me home if the mechanical fails -- this also make it easy to Dx fuel pump problems. This is the one I use...

https://www.autozone.com/servlet/UiBroker...C%7ENONE%7C%7EB
 
Sammy,

Why not first test the spark at a plug? Do you know that you have spark? If it really runs on ether, then you should have evidence of a spark. But I would check the electrics before I assumed it was fuel.

If you crank the engine a lot, you should have evidence of raw fuel at the plugs. Are they wet or dry?

If the plugs are quite dry after cranking, then you must have a fuel delivery problem. Do you know whether you have fuel to the carbs?

Good luck,

Jeff
 
[ QUOTE ]

And it cranks, will even start on starter fluid, but won't fire on its own. I'm thinking we have a fuel delivery issue. I hope I didn't bend and crimp a fuel line or something...or maybe I have crap in the line. Hopefully my fuel pump didn't freeze up.

[/ QUOTE ]
Hi Sam,
One of the lesser known facts about ether (starting fluid) is that it will compression ignite. Under the right conditions, it doesn't require a spark.
D
 
Never knew starting fluid will compression ignite (although I doubt the TR7 engine has enough compression to ignite even the most volitile mixture.)

As for the rest of the fault diagnostics, as I said, I haven't had a chance to look at anything yet. Was just about to pull and look at the plugs when my daughter woke up...

Since the car ran fine a month ago, when the carb mounts failed, I'd be surprised if the electrics failed. I can see the fuel pump getting gummed-up...but we'll have to look and trace it all. Planning on working on it wednesday during my writing block breaks.
 
So here's the update...
Fiddled with the TR7 today...Looked at the plugs and the front two were totally dry, the rear two were also pretty dry.

So it's obviously a few delivery bug. I pulled the fuel line to the front carb and put it into a cup and cranked. It filled the cup with fuel -- our pump is operational.

I pulled the tops of each carb, plus took out the pistons and sprayed carb cleaner down each hole. I tried -- and still won't start.

Ran out of time. Will get some more carb cleaner, and try taking out the pistons again, disconnecting the fuel lines and using an air nozzle to blow into the carbs after soaking more cleaner down there.

Anything else anyone can think of? I really don't think it's a spark problem.

I
 
Paul,
I wish I had good news. Did exactly what you said-- took off the tops and removed the pistons and thoroughly soaked carb cleaner down the jet holes. Still won't start. Also sent cleaner through the fuel line connectors.

I'm wondering if the floats came off their pins or something. Haven't had a chance to remove the carbs all together and take the float bowls off -- dreading doing this not just because of how long it takes, but also because I have never taken off the float bowls on 175CDs before. I guess there's a first time for everything...

...I just wish they were SUs, because the floats are so easy to get to!

It's just weird, but I'm thinking the floats (or the stromberg version of a grosse jet) will be all gummed-up.
 
Sammy,
You know these cars are quite sensitive. She knows how she is parked and realizing she can't get out anyway, isn't starting on principle.
The old saying, "rode hard and put up wet", not a chance of a cracked head?

Bill
 
You know TR6Bill is right, I didn't really start having bad problems with my TR7 until I let my wife move the car from the gas pumps to the parking area in Santa Nella CA. I think that my TR7 doesn't like women. You didn't let your wife or kids drive did you?
 
[ QUOTE ]
...Haven't had a chance to remove the carbs all together and take the float bowls off... but I'm thinking the floats (or the stromberg version of a grosse jet) will be all gummed-up.

[/ QUOTE ]

At the risk of being repetitive but I would be very surprised if something happened simultaneously & independently to both carbs. I would look instead for a single cause. You have confirmed fuel delivery beyond the pump -- but am not sure if you are certain you have correct spark. Sudden, complete failure to fire always makes me first suspect ignition -- plus it is so easy to check.
 
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