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View Full Version : It started! Can anyone help problem solve?



bitsilly
14-11-08, 05:14 PM
Kev popped round with his son last night and we started up the 383 that I built. The good news was that it started nearly straight away, keeping it going was a little harder!

First issue was the water temp showed 140c very quickly. I have since taken out the sender (from the head) and put it in a cup of hot water, then earthed it and the dial went to 140 again, later it got better but still showed 110c from water I could rest my finger in. I have ordered a new sender.

Next was the timing, the engine has been built with all new parts, none of which are OME except the block. At TDC the rotor arm points to the drivers front wheel. Am I right in thinking the dizzy should then be put on with the rotor arm pointing at the lead to cylender 1, we had problems with this so rotated all the leads one position round the cap. This seemed to help insofaras Kev could then get the timing marks somewhere like they should be!

Then the thing overheated and spewed, Next time it overheated and a hose to the overflow tank blew off spectacularly!

When switched off the engine overran and even spat flames (cool).

So the good news is that it runs, the bad news is not so well!

And big thanks to Kev for his help and stopping me having a wobbly!!

bitsilly
14-11-08, 05:31 PM
Forgot to say that Kev had a dial back timing gun, Kev if you are out there I found this:

Red hot headers is down to the ignition timing being too retarded. I know this as I had exactly the same problem. Get a dial-back timing light hooked-up, start the engine, bring revs up to 3,000rpm and set the timing light to somewhere around 34-36* using the dial on the back (hence, 'dial-back'). Rotate the distributor anti-clockwise using a GLOVED hand (unless you want to risk a very nasty shock) until the TDC mark on the crank balancer lines-up with TDC / 0* on your timing tab. This will set your total timing (ie. initial + mechanical) to 34-36* BTDC, which should be about right. Make sure the vac. advance (if equipped) is disconnected and plugged.

What did we leave it at Kev?

Lloyd Barnes
14-11-08, 06:30 PM
Forgot to say that Kev had a dial back timing gun, Kev if you are out there I found this:

Red hot headers is down to the ignition timing being too retarded. I know this as I had exactly the same problem. Get a dial-back timing light hooked-up, start the engine, bring revs up to 3,000rpm and set the timing light to somewhere around 34-36* using the dial on the back (hence, 'dial-back'). Rotate the distributor anti-clockwise using a GLOVED hand (unless you want to risk a very nasty shock) until the TDC mark on the crank balancer lines-up with TDC / 0* on your timing tab. This will set your total timing (ie. initial + mechanical) to 34-36* BTDC, which should be about right. Make sure the vac. advance (if equipped) is disconnected and plugged.

What did we leave it at Kev?

Hi, this was my car. Do check the timing as this was the problem with mine. The headers glowed red in under 60 seconds, so hot the temp sender melted! Point rotor arm at lead number 1, then rotate dizzy anti clockwise about an 1/8th of a turn to get some advance into it. Once you've got it running then the timing late will nail it properly

Just to keep your spirits up, even when I got that sorted it still ran like a bag of sh"t for the first 10 minutes or so (also a 383 built with all brand new parts apart from block). Its almost as if they need some time to clear their lungs and get everything settled in enough to run nicely!

On the positive side the huge overheat seemed to cause no lasting problems, now starts and runs just lovely and just wait till you take it down the road! :razz:

bitsilly
14-11-08, 10:12 PM
Cheers Lloyd,
I'll keep you posted! Can't wait to drive it.

Martyn-ak427
15-11-08, 07:16 AM
Agree with Lloyd comments below - Sounds like youve got some timing issues doesnt it. I was having similiar problems with my 393 Windsor. Silly question but make your not 180 out, also double, triple check all your leads are in the right place. I think im right in saying that as a rule of thumb hot headers means you are running your carb to lean.

Let us know how you get on.

Martyn

Lloyd Barnes
15-11-08, 10:36 AM
Agree with Lloyd comments below - Sounds like youve got some timing issues doesnt it. I was having similiar problems with my 393 Windsor. Silly question but make your not 180 out, also double, triple check all your leads are in the right place. I think im right in saying that as a rule of thumb hot headers means you are running your carb to lean.

Let us know how you get on.

Martyn

sounds like timing is well retarded, no way to get this right without a light. Add this in to the usual first start of an engine, rough running, smoke for a few minutes, factor in probably several grand on parts (don't tell the wife :razz:) easy to get worried!

bitsilly
15-11-08, 10:46 AM
Cheers Guys.
It seems the demon 650 carb is not set well out of the box. I may need to get more suitable sized jets and do some fiddling. I'm supposed to run it on 6 to 7 psi fuel pressure but if I try the engine bogs down, in fact it sounded best just before starving of fuel when the pump was disabled!
Have quadruple checked the leads and the order, I don't think I'm 180 out as I had a mare before setting the tappets 180 out and then corrected it and left it in that position.

Thanks again, especially for the 'keep your spirits up' bit!

kdavies3
15-11-08, 06:02 PM
Hi Ed,
firstly vac connections on the carb, can't remember which one we ended up on.

Brian (V8BJC) has he same carb and reliably assures me that it should be on the front port. (see my post in the engine section).:)
So if we're not already on it, move it. :)

The timing was set at 10 degs at idle vac off.

I'll pop back soon and we can double check using the recommended methods. :)

How are the air locks? :(

bitsilly
15-11-08, 08:19 PM
I have swopped the vac back to the front one. What I would like to do if this makes sense is to put it at TDC and then fit the dizzy in a position where the vac advance doesnt foul on the bulk head, then attach the leads appropriately.
Have been advised to up the fuel pressure and have a ballpark for replacement jets from realsteel.
Have replaced the temp sender but it still reads very high.
Have a bleed point for the hose but need to check if they are up to the pressure, wouldn't like it to explode again!
Be great if you have the time to pop round, owe you one!

kdavies3
17-11-08, 07:20 AM
No Worries ED!
I'll get to you soon.
I'll call you. :)

bitsilly
18-11-08, 07:12 AM
Good news!
I changed the sender and no improvement, it is reading too high a temp. But ignoring that I repositioned the dizzy to achieve that fabled 'pointing forward when at TDC'. Kev then helped me with my mind-flop and sorted the leads! Wound down the mixtures and upped the fuel pressure. Fitted a bleed point high in the cooling pipe....... and....now.....IT GOES AND SOUNDS SOOOOOOOOOO SWEET ! Really, superb.

ps Kev, fancy having a baby with me, let me know! Cheers Kev

And many thanks for all the advice gentlemen, couldn't have done it with out you!