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Engine Specific Info and Questions => IDI Engine => Topic started by: ryanp on March 14, 2010, 03:12:02 pm

Title: Do i need a little more advance?? cold and hot start probs
Post by: ryanp on March 14, 2010, 03:12:02 pm
My dad's newly installed engine needs the cold start lever for a nice start up when cold (well above 0degrees, so not freezing!) it runs rough and also smokes quite a bit for a minute or two, am i right in thinking this points to needing a little extra advance? I have it set to .95mm.

Also, it takes quite a bit of cranking when warm and the glow plug light does not illuminate (it does when cold) is this the coolant temp sensor? i disconnected it and it made it worse?

Cheers

Ryan
Title: Re: Do i need a little more advance?? cold and hot start probs
Post by: westcoaster on March 14, 2010, 09:15:45 pm
Let me know what you do to fix this...

I had a LOT of advance. I needed the cold start lever. A board member and I set it back to 1.0mm and I still need the cold start lever (he did too)

I'm starting to think it's normal...

As far as the starting when hot.

I crank the engine (little more than a bump on the starter) if it doesn't catch right away I stop cranking. Turn the key off and bump the starter again. It usually catches immediatly then. where if I kept cranking it wouldn't catch so fast.
Title: Re: Do i need a little more advance?? cold and hot start probs
Post by: ryanp on March 17, 2010, 09:10:09 am
Sounds very similar, anyone have any ideas?

Ry
Title: Re: Do i need a little more advance?? cold and hot start probs
Post by: rabbitman on March 17, 2010, 12:02:31 pm
Does it run rough and smoke WITH the cold start out? I don't see anything wrong with using the cold start to smoothen things out (that's what it's for) but it should start AND run good with it out.

If I start mine at 0F without plugging in it starts kinda slow and after it starts running I have to pull the cold start to get a halfway smooth idle. It cranks slower with the cold start out so I don't oull it 'til it's running.
Title: Re: Do i need a little more advance?? cold and hot start probs
Post by: ryanp on March 17, 2010, 02:34:34 pm
yeah with the lever out it's a little smokey but nothing major and much smoother, my main worry is the fact that it's only mild and it needs it, when it's down to -10 i dont want to get the spanners out!

Title: Re: Do i need a little more advance?? cold and hot start probs
Post by: snakemaster on March 17, 2010, 05:06:45 pm
what miles are on it , injector nozzles could be a bit worn,  good CR in the engine on all 4
Title: Re: Do i need a little more advance?? cold and hot start probs
Post by: ryanp on March 18, 2010, 01:39:48 am
it's done about 105k, was a good runner till i td'd it, lol.

I had a feeling about the injectors, i'm gonna run some Forte through it i think see if that makes it a little better.
Title: Re: Do i need a little more advance?? cold and hot start probs
Post by: orengutan on March 18, 2010, 10:41:52 am
complete newb question: how does the cold start handle affect the injectors?
Title: Re: Do i need a little more advance?? cold and hot start probs
Post by: rabbitman on March 18, 2010, 11:29:50 am
complete newb question: how does the cold start handle affect the injectors?

It just advances the injection timing a little bit.
Title: Re: Do i need a little more advance?? cold and hot start probs
Post by: orengutan on March 18, 2010, 11:40:40 am
in what way? when I bought this car I found out I had to use the cold start handle in pretty much every cold start (15c and lower). which I thought was sketchy, but I had other things to worry about at the time.

now I'm trying to diagnose a floating idle issue (1000-1100 idle when cold, 950 when warm) and I suspect these may be related.
Title: Re: Do i need a little more advance?? cold and hot start probs
Post by: Smokey Eddy on March 18, 2010, 02:43:26 pm
hot start problems i found were due to a serious lack of compression.
Title: Re: Do i need a little more advance?? cold and hot start probs
Post by: rabbitman on March 19, 2010, 01:04:46 am
hot start problems i found were due to a serious lack of compression.

That is true, I've discovered that retarded timing can also make it crank a bit longer before starting, couple that with lowish compression and you got a problem. A cold engine is pickier, so it might start hard but run good/ok once it's up to temp.
Title: Re: Do i need a little more advance?? cold and hot start probs
Post by: theman53 on March 19, 2010, 05:15:39 am
My favorite hot/cold start problem was a leaky fuel system. Not bad enough to show, but bad enough for it to loose prime. Add a weaker compression engine that was otherwise good to start and I had some long cranking before starts.
Title: Re: Do i need a little more advance?? cold and hot start probs
Post by: Smokey Eddy on March 19, 2010, 11:49:43 pm
for the longest time before i had my 1.9 head - my car would roll start instantly but never start with the starter when it was hot. the compression was just non-existant.
when it was cold however it would actually start a little easier. i dont know how that works. colder air more compression? hardly makes sense.
Title: Re: Do i need a little more advance?? cold and hot start probs
Post by: ryanp on April 24, 2010, 12:50:37 pm
Still having this issue, fires on the button when cold but takes a good few turns when warm (E.g. left for 30+mins) but will fire straight up if its only been left for a couple of minutes!

Any one have any thoughts before i try to make an adapter for the compression tester? the engine was stood for a while prior to the conversion, could it be stuck rings?

Quite a bit of ££ has been put into stuff like belts, seals pump build ect so i'd like to keep this of possible!

Cheers!

Ry
Title: Re: Do i need a little more advance?? cold and hot start probs
Post by: lovinthedeez on April 24, 2010, 03:34:19 pm
was the piston height measured during the rebuild.  was a three notcher head gasket thrown on there?
Title: Re: Do i need a little more advance?? cold and hot start probs
Post by: ryanp on April 25, 2010, 09:06:33 am
the head was never split apart from the block, The engine ran fine in the donor car a few months before!

Very strange!
Title: cold and hot start probs!!
Post by: ryanp on April 29, 2010, 01:28:45 am
Does it sound like the engine needs replacing with a better unit? i've got to tear the gearbox off again to do the rear main seal so it's not much more work really!

Thanks!
Title: Re: Do i need a little more advance?? cold and hot start probs
Post by: ryanp on April 30, 2010, 12:36:18 am
anyone? dont want to put any more time or money into this if i might aswel swap it out!!
Title: Re: Do i need a little more advance?? cold and hot start probs
Post by: ryanp on May 06, 2010, 01:06:53 pm
??
Title: Re: Do i need a little more advance?? cold and hot start probs
Post by: rolo on May 06, 2010, 11:18:57 pm
Ryan, what you need first are compression test results from a 500 psi+ guage. Still want to know what you`ve done to that Z.