Triumph Repair: TR7 Not Starting, crank pulley, vacuum hoses

Question
Hi Howard;

We consulted about a TR7 water pump installation this past summer, and I'd like to consult you about a related issue.  I finally finished the water pump installation on my '79 TR7 and now the car will not start.  While working on the water pump I did some additional work, which included the installation of a new Pertronix  and a different intake manifold on the car (bought it on Ebay, it was cleaned up and painted...it is for my year car).  The car has the Stromberg carbs installed.  With full choke on the car will not start...it seems like it wants to start but will not fire.  It will not even start with starting fluid.  Here are some checks I have done:

1) It has spark at all 4 cylinders (checked by pulling plug wire and holding it near a ground while engine cranked), and it appears to be good spark (long and blue-colored).

2) I had to remove the distributor to install the Pertronix, so I re-checked the firing order.  With the motor set at TDC (crank pulley notch at O on the scale, camshaft index marks are all lined up) everything appears to be in order.  The rotor is pointing approximately toward the intake manifold stud as the Bentley Manual (ROM manual) indicates.

3) The fuel pump is working (flowing fuel).

4) All vacuum hoses are hooked up and I don't think there are any leaks(but that doesn't mean there isn't any).

5) Carb needles are set in an intermediate position (1 full turn out from their highest setting).  Diaphragms in the carbs are intact.

6) Carb pistons free to move, return to the "down" position easily and quickly.

7) I haven't checked compression but it was 160 psi across all 4 cylinders before the water pump repair.


These are all the checks I've done.  I really don't know what else to check.  Since the car will not start even on starting fluid, it suggests that somehow the motor is not getting fuel.  Do you have any ideas or suggestions?  I would really appreciate the help.

Thanks!

Matt M.
'79 TR7

Answer
Hi Matt,

Even though you have done a lot of work and testing, when you have a engine that does not start you need to start from scratch and don't leave any stone unturned and you MUST do the tests in the correct order.

If you had brought the car to me and told me all you did, I would still have to do all of the tests and in order.

Rerun the compression test with the throttle open.

Compression always first and even if it was good yesterday or last week you still need to run it again. Also run a intake manifold vacuum test (throttle closed and choke off)

If it is still ok and only if it is ok on compression and vacuum can you proceed to ignition.

Next is Ignition - Run a preliminary test by removing all four plugs and put the plugs on their plug wires and lay them on any metal part of the engine. Then put your thumb over #1 plug hole and have some one spin the starter. As the #1 piston comes up it will blow your thumb off of the plug hole and make a "POP" noise. If the spark at the plug seems to be made by the "POP", it is close to correct timing enough to start. However, If you see "Spark"-"POP" or "POP"-"Spark" the timing is off and may cause it not to start. Do each of the four cylinders the same way. Reset the ignition timing if it is off.

Any time that you can't start an engine and keep it running on spray starter fluid, you have either a compression, vacuum or ignition problem.

Never try to look for any specific problem or part. Always test systems first and in the correct order. Then when you ID the failed system run tests on that system only.

If you follow that, you can never fail to find any problem.

Howard