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Discussion Starter · #1 ·
Can anyone help I have a 1760 crossflow in a 100e , just had to put new rings in it as others had snapped , seam and sounds nice now ,
Vulcan head
38d gas carb
Just brought an electronic ignition for it ,waiting for it to arrive .
But start it up move the dizzy until it revs and pulls through all the gears as it should , but it won't start sounds like a dead battery , but its a new heavy duty one , alter the dizzy so it starts spot on , then it holds back going up the road ?
Any ideas what timing I should be looking for ?
Was thinking of blanking of vacume advance .
Cheers Dazza
 

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when you say 'like a flat battery' is it trying to hold/kick back as it try's to fire? if so then retarding the ignition is right. but then it holds back when driving as if it's too far retarded. sounds as if you need a new dizzy with the advance curve tailored to the engine. you could file the advance weight stops in the dizzy to give more total advance which would allow you to back off the initial advance for starting.
 

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Discussion Starter · #3 ·
Cheers Neil , it really sounds like a dead battery hardly turning over , no pops or bangs , battery in boot , leads getting hot and so is solenoid , alter dizzy and it spins over real nice and quick . Need to put electronic ignition on it and get it set up on the rollers .
Also it's still got the old style screw starter motor, so may look at changing that also .
 

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I'm Not Jed Clampett
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Worth checking that the centrifugal advance isn't seized or sticking if you haven't already; with the cap off, just grab hold of the rotor arm, you should be able to turn it in the direction of the distributor's rotation, when you let it go it should spring back. If it is seized or sticky, remove the small screw that's under the rotor arm and put a few drops of 3 in 1 or ATF down there and waggle the rotor arm back and forth to free it off before putting the screw back in.
 

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Depends on the cam being used but normally a performance Ford 4 would use 10 btdc initial advance and start without any slow cranking. You normally dial in a MAX of 16' total advance for best performance. I've played about with dizzys on these and although many will fit and work they are HUGE differences in the timing curve. There's difference between standard 1600 and GT version for starters.
 

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Discussion Starter · #7 ·
No markings on cam kev , believed it was a custom grind by Vulcan .
Now the engine has decent compression its a pig to start .
The old rings were snapped and it was blowing oil out the dip stick , so we had to machine bigger grooves in pistons to get a good set of rings to fit nissan 85mm now. And it just does not like starting . May have to do some dizzy research it has a fomoco on at the moment .
 

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Snapped rings make me think the timing has been an issue before and hammered them to death? My old man ( Spitfire mechanic) always told me " Don't just fix it, find out WHY it broke in the first place " ;)
 

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Discussion Starter · #10 ·
We came to the conclusion the rings were broke because !
Top ring gap was 1.8mm
Ring was only 1.0mm
No one seems to make a 1.8mm 85mm ring
So we went up to 2.0mm on the top and middle ring
4.0mm bottom ring
That's what we believe also had a bit of burn by on the pistons was running twin 40s that needed setting up, so went over to a 38d gas . That's seems a lot lot more reliable , don't sound as good but . :)

Cheers bluffin looking at getting a new starter , replace the earths also , live is a nice size cable also.
 

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We came to the conclusion the rings were broke because !
Top ring gap was 1.8mm
Ring was only 1.0mm
No one seems to make a 1.8mm 85mm ring
So we went up to 2.0mm on the top and middle ring
4.0mm bottom ring
That's what we believe also had a bit of burn by on the pistons was running twin 40s that needed setting up, so went over to a 38d gas . That's seems a lot lot more reliable , don't sound as good but . :)

Cheers bluffin looking at getting a new starter , replace the earths also , live is a nice size cable also.
I would be curious to know what cranking pressure you have. If you have a compression tester see what readings you get, it seems the top ring land has been getting hammered because no one would put a 1mm ring in a 1.8mm groove. You might find your piston/head combo is wrong a your comp ratio is too high. Quick easy check.

Bob
 

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Discussion Starter · #12 · (Edited)
I will do a test also tonight and put up results ,
On spinning over with timing out , it spins up really well no hesitation at all . Sound fine , but going down the road it's holding back under load .
All four pistons the top groove is the same all the way around as in machined like it, so signs of damage .
Its a flat head with very deep pockets in the pistons , aftermarket ones .
 

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I will do a test also tonight and put up results ,
On spinning over with timing out , it spins up really well no hesitation at all . Sound fine , but going down the road it's holding back under load .
All four pistons the top groove is the same all the way around as in machined like it, so signs of damage .
Its a flat head with very deep pockets in the pistons , aftermarket ones .
Deep pockets or a deep dish? Crossflow fords should have a bowl in the top of the piston Ford Escort 1600 711m standard pistons x 4 new 1971 onwards | eBay

Bob
 

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I'm Not Jed Clampett
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They should provide the "squish" you need to avoid needing huge amounts of total advance. I did some machining work on a really big bore xflow motor which had flat top pistons (didn't have mad compression because the pistons didn't come to the top of the bore). It had the usual xflow flat head face, it gave quite good power but it needed 45+ degrees of total advance to make it work because there wasn't any "squish" to push the mixture towards the spark plug on the compression stroke.
 

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you say the leads/cables are big enough but also you said they get hot as does the solenoid. sounds like they need to be bigger, try putting a long jumper cable from the battery to the solenoid so you've doubled up the lead and see if there's any improvement.
 

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Discussion Starter · #17 ·
Dizzy returns as it should , not had time to do compression test yet.
Also put a jump pack on solenoid and still a pig to start , so waiting for new starter and electric ignition for now .
Cheers all
 

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TechnicalTom
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Not a cure but a worthwhile " fix" till you sort things out(,Megajolt maybe,) run a wire to the ignition coil + side through a switch mounted on the dashboard , then crank the engine with the key and then throw the coil switch.This is a popular mod when the distributor is " locked out at max."ignition timing advance.
 
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