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3 hours ago, Steves_TR6 said:

Hi Waldi, are you SURE the timing is right ...... :-)

That's a good advice, timing's got to be close or the engine won't run, valve timing and ignition. It's all too easy to get the ignition timing out by 180 degrees and the engine may cough occasionally while cranking but it won't run. The injection timing is less critical, if the metering unit is timed wrong the engine will usually start but won't run as well as it should. I almost hesitate to say, but are you sure the plug leads are connected right, if one or two cylinders fire but not the rest? Sorry, I'm not trying to patronise but sometimes in the heat of the moment we overlook the simple things.

Waldi, I have felt the same frustration but don't worry, you know the bottom end of your engine is good because you have oil pressure. A logical approach going through all the variables (valve and ignition timing again, fuelling too) will get the engine running in the end.

I rebuilt my GT6 engine a few years ago. When the big moment came, it wouldn't start, so here's my little story of a simple thing I got wrong... There was a spark, the carbs were full of fresh fuel, everything was connected but no joy... not even a fart! In the end, I found I hadn't adjusted the choke cable properly and the mixture wasn't rich enough to start a cold engine. Such a simple thing. As soon as I tightened the choke cable it started, and has run beautifully ever since. I'm sure you will find an equally straightforward explanation for your new engine's reluctance to fire.

 

Good luck,

Nigel

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And i spent literally months trying to track down the cause of bad running on an v8 petrol engine in a boat years ago...... condenser!

i’d physically set the engine to tdc on compression on cyl 1, using a tdc probe and checking valves closed.

then check the rotor arm is pointing to cylinder 1.

then check order of ht leads from there

next, what sort of ignition are you using Waldi, do you know it works?

fuel ladt, as ‘90% of fuel problems are actually ignition’ !

good luck, looking forward to your success !

steve

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Thanks Nigel and Steve,

I’m confident it will be something obvious.

end of this week I will continue.

std ignition, and nice blue sparks. Will double check timing with valvecover off if the diesel start does not do it.

cheers,

Waldi

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A squirt of something highly inflammable into the butterflies whilst cranking can also start the whole process. I use this recently on a 125 Suzuki that had not run for a long time. I found a can of carb cleaner, it worked a treat. This was after two days of intermittent of cranking including jump starting it from my Volvo which did not produce a cough or splutter.

Mick

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Thank you all.

I will get a can of what we call “diesel start” first, and check the ignition again, I’m aware it revolves anti clock-wise. I’m so convinced the timing is correct, so probably it isn’t :)

It not be before Friday before I can work on it again.

Regards,

Waldi

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Hi Ed,

Thanks and yes, I will do that (again). With valve cover removed to verify both valves of the #1 Cyl are closed.

Waldi

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Just FYI Waldi , the timing marks on the front pulley shouldnt be trusted.

mine had slipped by 8 degrees, as verified against a piston stop confirmed tdc.

suggest you check yours so as to be sure !

steve

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Hi Steve,

I did that during the rebuild as this forum triggered me:)

I was within 1 degree of the original mark. I used the micrometer approach to find the TDC, as also described here many times.

wish the forum was there in 1993 with my first TR6.

Waldi

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Hi Waldi,

 

to check the ignition timing:

- Remove valve cover

- Turn engine by hand to TDC

- Check if both valves of cylinder 1 are closed, rockers should have minimal movement

- If not turn crankshaft another 360 degrees and check valves

- Remove distributor cap, from the position where you are standing the rotor arm should point at 7 o´clock

- At this position lead 1 should be in the distributor cap

- Then check the order anti clockwise 1-5-3-6-2-4

 

Timing of the metering unit does not matter, my MU is 180 degrees out and seems to run better at idle. Did you check the fuel pressure?

 

Regards Peter.

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Thank you Peter, I think I have set ign timing exactly like that when I assembled the engine. MU also set according wsm.

I have not measured fuel pressure yet, have a new Bosch pump and reconditioned PRV, MU and injectors, so for now I assume fuel pressure is ok.

Measuring it is on my list after “diesel start”  and ign timing.

Waldi

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Update:

Yesterday I spent a couple of hrs on the TR.

1) checked timing (valves closed and #1 igniting: ok. Checked static timing, 8-10 degr btdc, so ok for now.

2) then checked sparks, nice blue.

3) replaced the (new) condenser with another new one; they measured 190 and 250 nanofahrad, should be 200 according to wsm, so think ok.

4) used Start-pilot (ether) with minimal or no improvement. 

5) started again with another running car helping the battery so had quicker starting (higher revs), this made some difference, but stil no luck.

6) checked compression ratio, just on one cylinder: 150psi/10.5 bar. So ok.

7) removed 2 injectors (#1&2), both gave fuel, in a kind of cone, but not really a fine mist. I’m lacking experience on what good looks like.

 

Next on my list:

check strength of spark, can it bridge more than say a 5 mm gap?

check fuel pressure at MU.

(get drunk if still no luck)

Any hints, ideas are welcome, as always.

 

I have a little confession to make:

I connected the white wire to the coil (feed, 12V) directly to the -ve pole of the coil (yes, stupid). On that pole was also the wire to the dizzy.    Result: the little woven (flexible) wire inside the dizzy to the points burnt out (took 5 seconds or so), so I have replaced that. I do not think it damaged the coil, and the little plastic insulators still look ok, but thought I’d mention it.

Thanks,

Waldi

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This might sound stupid and forgive me if you have done this; make sure your distributor is seated properly and is rotating when the engine is cranked.  I had mine out once and didn’t tighten the clamp enough and it lifted enough for the drive dog to come out of the gear and stopped me dead on the side of the road. Good luck!

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Fairly recently had to start a newly rebuilt engine. Had issues with air in the fuel system, and had to bleed the injectors as mentioned. Once this was done we got a lovely high pressure fine mist cone of fuel into a jar.

Not sure if this is even possible but is the rotor arm pointing a lead 1 when it should, apologies if this sounds a bit silly but just a thought.

 

Good Luck

 

Dave

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Charly,

thanks, the dizzy housing is tight and cannot rotate.

Dave,

The rotor “front edge” is pointing towards #1 and both valves of #1 are then closed. Compression ratio 150psi makes me pretty confident valve riming is also ok.

My spray pattern is not really a fine mist, but a bit difficult to see at night, will test again tomorrow. i only tested #1 and 2, will check all 6 tomorrow.

Thanks,

Waldi

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Hi Waldi

Give it fuel, air and a spark at remotely the right time and it’ll run!

so...

Fuel, after cranking whip out the spark plugs, are they all wet or at least smelling of fuel?

Is the fuel enrichment lever operating?, need this to cold start.

Air, you’ve not blocked off the air filter / plenum in any way?

are the throttles opening, probably need a bit of throttle to ‘catch’

sparks, you seem to have thoroughly tested timing, is the coil good?

do you have a ballast system? If so perhaps bypass it for testing.

sometimes the ballast fails so when cranking theres a spark but not when you release the key.

good luck, what joy it will be when the motor runs !

 

steve

 

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Hi Waldi, having recently started mine from a rebuild, and had unlimited starting and running issues I found the following worked for me once I was happy I had everything timed correctly and a good spark...

Disconnect the main fuel line to the MU. With the help of a friend and the pipe in a collection pot run the pump for a short period to ensure the system from the tank is fully primed

Attach fuel pressure gauge to MU and set to recommenced psi (monitor during the cranking process)

Set butterflies using cigarette paper

Open MU fuel lever fully with the butterflies opening correctly on the cam

Use no additional throttle until it catches 

good luck Alan

 

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Hi Steve, thank you, see below  responses:

Fuel, after cranking whip out the spark plugs, are they all wet or at least smelling of fuel? They are not wet, but I smell fuel on the plugs. This makes me think why they are not wet. Am preparing my fuel pressure gage, measuring is a job for tomorrow, hopefully.

Is the fuel enrichment lever operating?, need this to cold start. Yes, if I pull the choke, the lever on the MU is moved. Have tried with and without choke, and with ether (start-pilot)

Air, you’ve not blocked off the air filter / plenum in any way? The plenum is not installed at the moment to be able to see what's happening

are the throttles opening, probably need a bit of throttle to ‘catch’  I screwed them "cracked open", but more than a cigarette paper.

sparks, you seem to have thoroughly tested timing, is the coil good? Coil primary resistance is 3 Ohms so sit hould be ok (no coil, and no resistance wire in the loom)

do you have a ballast system? If so perhaps bypass it for testing. No, CP harness so no resistance wire in the loom, and double checked the voltage while cranking at the coil, it was still 10.5 V (same as battery while cranking) We also used a separate battery direct to the coil with 12.5 V, this made no difference.

sometimes the ballast fails so when cranking theres a spark but not when you release the key. I understand what you mean, but I can crank as long as I want, but it wont pick up.

good luck, what joy it will be when the motor runs ! Thanks for your help, in the end I (we) will crack this nut!

Best regards,

Waldi

 

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16 minutes ago, sheldricka said:

 

Disconnect the main fuel line to the MU. With the help of a friend and the pipe in a collection pot run the pump for a short period to ensure the system from the tank is fully primed

Attach fuel pressure gauge to MU and set to recommenced psi (monitor during the cranking process)

Set butterflies using cigarette paper

Open MU fuel lever fully with the butterflies opening correctly on the cam

Use no additional throttle until it catches 

good luck Alan 

 

Hi Alan,

I will do that tomorrow, I think all air is out of the system to the MU, but checking does not harm:)
The PRV pressure should be correct, it was set by Neil Ferguson, but I will double check.
Your comment about setting the butterflies with cigarette paper makes me think, currently they are just "cracked open"; I just thought that would be ok, and I was planning to make adjustments once it was running, but will do this first.

I have not connected the cold start cam on the throttle linkage yet, but will also to that (thought I could do without, and just "play" the engine. Is it that important?

Will not use additonal throttle until she catches.

Thanks for your pointers too Alan.

Waldi

 

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Waldi, youll need the throttles more open than ‘a crack’ to start a cold engine 

i, and many others, do not have the ‘fast idle cam’ connected, ie the ‘choke’ just pulls the mu lever

to start i pull the ‘choke’ fully out

turn the engine over and as soon as it tries to fire i open the throttle a bit and it catches.

have you been opening the throttle when trying to start the motor?

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Hi Waldi

You could first try cracking open the flex fuel pipe to the Mu to bleed the system of air. This could stop you getting full pressure to the injectors. A very fine mist from the injectors could be air in the system or low fuel pressure. You should feel a firm pulse through the injector fuel  lines.  Have you got the Lucas service and fault finding manual for the Pi system. I can send you a link if you haven't. Might be of help.           Best Luck

Roger

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