Roadkill's 1983 Chevy Z28 - (Work Starts on Page 5)

[Roadkill]

Quoting: Roadkill

and am investigating the "correct" timing . . . .

Apparently ignore the vacuum entirely is the vibe I get - just bung it and forget it while timing.

36* advance, total all in @2,500RPM.



Think I need to check if I am indeed all in @2,500RPM.  

I think we were aiming for more like 6* Initial, 20-something total.

Ian - do you remember what we were going for ???

[FUBAR]

Looking very

[Cunning Plan]

Wow awesome work!

Who's lockup is that? Works? You must have an awesome boss!

What are the two contaners above the wheel-arches? Coolant and screenwash?

[ianjpage]

Quoting: Roadkill

Have ordered the other front running light from the states and am investigating the "correct" timing . . . .

Do we have a "minefield" smiley.

Cool not long before she's all "lit" up then hehe

Quoting: Roadkill

Apparently ignore the vacuum entirely is the vibe I get - just bung it and forget it while timing.

36* advance, total all in @2,500RPM.



Think I need to check if I am indeed all in @2,500RPM.

I think we were aiming for more like 6* Initial, 20-something total.

Ian - do you remember what we were going for ???

Hmm interesting, specially the difference it made, then didn't make when we had it off / on!

36* - wow that was more that we were going for - we were aiming for about 4-6* @ idle  and yeah about 20-25 i think at 2500, which we wern't far off i think...

Quoting: Cunning Plan

Who's lockup is that? Works?

Roger 1

Quoting: Cunning Plan

What are the two contaners above the wheel-arches? Coolant and screenwash?

Roger 2

[Andy]

Quoting: Cunning Plan

What are the two contaners above the wheel-arches? Coolant and screenwash?

Something that makes me smile, I reckon the guy that designed these bays like symmetry, the coolant bottle is about 50 times bigger than is needed and the screenwash bottle takes a good 5 litres to fill!

[Roadkill]

UPDATE -

Re-fitted the lower chin spoiler last night . . Plan to fit the air dam tonight.

Been charging up the battery to check the water pump . . . It's working fine (as is the tach and oil pressure seems good also) so I'm assuming the funny readings I was getting was due to low voltage ????

Dunno.

When we fire her up to re-time her we'll have to bring out the multimeter and see what's going on . . .

Quoting: ianjpage

Hmm interesting, specially the difference it made, then didn't make when we had it off / on!

That's the thing.  Vacuum only really makes a difference at idle - which is why the idea of ignoring it seems sensible as you're more interested in what's going on beyond idle/low revs.

I think we need to slowly run her up to 3000RPM to find out when the Mechanical advance is "all in" (should be around 2400RPM I think.
If this is the case we'll set the timing at 2500RPM and then see where idle sits after.

If we're not all in by 2500RPM then I may need to look at different weights . . .

The frustrating thing is, ironically, with all the new stuff that's been put on the engine the dizzy is the ONLY piece that I re-used from the origianl 305ci small block.  And that came with the car so I don't know the make or the age of it . . . only that it's aftermarket and it works.

Quoting: Andy

I reckon the guy that designed these bays like symmetry

I know.  I brought new tanks as they're so prominent.  Was well worthwhile.

Quoting: Cunning Plan

Who's lockup is that? Works? You must have an awesome boss!

Yeah, they're helpful.  My MD doesn't care either way but my Director does complain a little.
I can't moan, though.  It's helped out no end and the rate of progress has been second-to-none over the last few weeks - even with the snags we've encountered.

[Jamieg285]

Quoting: Roadkill

That's the thing. Vacuum only really makes a difference at idle - which is why the idea of ignoring it seems sensible as you're more interested in what's going on beyond idle/low revs.

I think we need to slowly run her up to 3000RPM to find out when the Mechanical advance is "all in" (should be around 2400RPM I think.
If this is the case we'll set the timing at 2500RPM and then see where idle sits after.

If we're not all in by 2500RPM then I may need to look at different weights . . .

Before you start, make sure it's all clean and the weights move freely.  I'd look at the springs before changing the weights, as these will affect how soon/late the weights open up. There's 3 pairs of springs in a kit and you can mix them as well to get extra combos.

Ideally you set total timing as you say (although I would expect to be looking higher - say 32-34) all in by 2.5K. The actual figure will be what the engine likes best, not a pre-prescribed figure.  I'd look into this more if I were you, as the figures are quite a bit different.  

Then look to get an adjustable vac-advance can to sort out the timing you want at idle.

[Titsy]

Quoting: Roadkill

Been charging up the battery to check the water pump . . . It's working fine (as is the tach and oil pressure seems good also) so I'm assuming the funny readings I was getting was due to low voltage ????

My suspicion is that the alternator isn't spinning fast enough at idle to charge the battery...

[ianjpage]

Quoting: Roadkill

UPDATE -

Re-fitted the lower chin spoiler last night . . Plan to fit the air dam tonight.

Cool, prob looks a lot more like it's old self now then

Quoting: Roadkill

Been charging up the battery to check the water pump . . . It's working fine (as is the tach and oil pressure seems good also) so I'm assuming the funny readings I was getting was due to low voltage ????

Dunno.

Hmm very odd but good that they are working now - must have been the draw of current / voltage on the battery when it got so low it couldn't hack it!

Quoting: Roadkill

When we fire her up to re-time her we'll have to bring out the multimeter and see what's going on . . .

Yeah be intersting but having a chat to titsy on new year after you left and we both of the opinion that sitting it idle to tune it for so long wasn't turning the alt. fast enough to generate a good charge, so hopefully at rev's it should be OK but then just have to be careful when idling as may not create enough charge.

Quoting: Roadkill

That's the thing. Vacuum only really makes a difference at idle - which is why the idea of ignoring it seems sensible as you're more interested in what's going on beyond idle/low revs.

I think we need to slowly run her up to 3000RPM to find out when the Mechanical advance is "all in" (should be around 2400RPM I think.
If this is the case we'll set the timing at 2500RPM and then see where idle sits after.

If we're not all in by 2500RPM then I may need to look at different weights . . .

The frustrating thing is, ironically, with all the new stuff that's been put on the engine the dizzy is the ONLY piece that I re-used from the origianl 305ci small block. And that came with the car so I don't know the make or the age of it . . . only that it's aftermarket and it works.

Sounds a sensible plan, and as you say if the bit yer worried about is at throttle, not idle, then time it there

[ianjpage]

Quoting: Titsy

Quoting: Roadkill
Been charging up the battery to check the water pump . . . It's working fine (as is the tach and oil pressure seems good also) so I'm assuming the funny readings I was getting was due to low voltage ????

My suspicion is that the alternator isn't spinning fast enough at idle to charge the battery...

Dang you beat me to it by seconds lol

[Titsy]

Seconds... Pahh, it was almost a full minute!

[ianjpage]

Quoting: Titsy

Seconds... Pahh, it was almost a full minute!

i just said seconds, i didn't say how many hehehe :p

[Roadkill]

Quoting: Jamieg285

Then look to get an adjustable vac-advance can to sort out the timing you want at idle.

Good idea.

Need to find out what make/model it is, really.  I've looked before but don't remember seeing any P/N's on it . . .

Quoting: Titsy

My suspicion is that the alternator isn't spinning fast enough at idle to charge the battery...

We can check this with a multimeter, can't we ?

[Andy]

Quoting: Roadkill

I know. I brought new tanks as they're so prominent. Was well worthwhile.

Ah right, in which case, how to you remove the coolant one? Theres one lower bolt that you can remove, but it seems to held further up the wheel arch. Before I go at it with a crow bar and brute force, is there another bolt somewhere I'm missing?

[Roadkill]

Yeah, on mine there's one at the back, too on a little tab just down from the top.  From memory they're held in with black plastic screw-rivet thingy's.
You should be able to see them clearly from underneath with the arch liners out.

(EDIT - You can make it out on the picture directly above)

That said you can see mine easily . . I can't remember what used to be there to obscure the view . . .

I had the room and replaced them with M6 stainless bolts and nyloks.

[ianjpage]

Quoting: Roadkill

Quoting: Titsy
My suspicion is that the alternator isn't spinning fast enough at idle to charge the battery...


We can check this with a multimeter, can't we ?

yup

[Andy]

I guess you're running a single wire alternator with an external voltage regulator?

[Roadkill]

No.  Or not as far as I know.

It's a standard Delco jobbie from memory.

[Roadkill]

Voltage on the gauge at idle with choke (900RPM) = 10.4V

Voltage on the gauge at anything up to 4000RPM = 10.4V



In other words engine speed isn't affecting the output of the alternator ???????

EDIT - Some pictures from lunchtime . . .

Nosecone, Chin and Air Dam fitted.  (C.P - Note the new fixings on the nosecone.   )



Front view is looking a lot more normal with the lower chin on . . . still looks a bit funny being so far up in the air . . .



Next job is to remove the steering rack and start cutting the old brackets off so I can measure-up properly to fabricate and fit the new ones . . .
I'll do a little bit of this this evening, then hopefully we can spend a hour or so getting the timing sorted and figure out what's going on with the alternator over the weekend at some point . . .

[ianjpage]

Quoting: Roadkill

Voltage on the gauge at idle with choke (900RPM) = 10.4V

Voltage on the gauge at anything up to 4000RPM = 10.4V

Hmm that's not good - should be nearly 14v i think when revving...something not right there....

[Andy]

Just been through the whole alternator saga with mine.

In theory the voltage should have a little fluctuation between idle and being revved, but either way it should be north of 13v at idle. This really is the least for the battery to be getting any chance of being recharged. Do also bare in mind at idle an alternator barely makes enough current to recharge the batter with any accessories running.

If you're getting 10.4V I would say that the alternator is almost definitely kaput or if it is the original Delco unit, is not being feed a decent reference or exciter voltage.

Do you have a multiplug connected to the unit? If its the same set up as mine I can write down the fault finding procedure I did on mine.

[Roadkill]

Quoting: Andy

with any accessories running

I don't have any accessories.

I've just pulled the paperwork on the alternator . . . apparently it's a "Load Boss" CS 130 GM alternator.

I brought it from eBay (US) as a refurbished unit . . .

The seller is still on Ebay but doesn't sell these units anymore (or at the moment).

[Andy]

Quoting: Roadkill

I've just pulled the paperwork on the alternator . . . apparently it's a "Load Boss" CS 130 GM alternator.

I got a link to a service manual for that here somewhere...

http://alternatorparts.com/cs130_sbpage1.htm\" target=\"_blank\" rel=\"nofollow\">http://alternatorparts.com/cs130_sbpage1.htm

It also means its the same as mine. In which case you maybe looking at a duff rectifier or an insufficient exciter charge.

Are you good with a multimeter for testing it? It is easily accessible? Can't see it in any of the engine bay photos

[Andy]

Also, that 10.4v might be a false promise, if you're reading that off the battery then the alternator may actually not be putting anything out at all. The only way to tell if the alternator is outputting anything is by disconnecting the output lead but keeping the multiplug connected. Then measure the output post to the engine block or negative terminal.

[Roadkill]

Quoting: Andy

Are you good with a multimeter for testing it?

No, crap.  But I know a man/some men who can.  

Quoting: Andy

It is easily accessible?

Oh, yes.

Quoting: Andy

Can't see it in any of the engine bay photos

It's on a re-positioned bracket, slung low.  But shed loads of room !

Quoting: Andy

Also, that 10.4v might be a false promise, if you're reading that off the battery then the alternator may actually not be putting anything out at all.

Believe it or not I had actually thought of that and even partly assumed that - based on my limited knowledge.

Quoting: Andy

The only way to tell if the alternator is outputting anything . . . . . .

Will check, ASAP.

ON A SEPARATE NOTE :

Steering bracketry is off the K-Member . ..  didn't need cutting . . . a few clouts with a nylon mallet and they broke of leaving very little behind . . . a quick buzz with a linishing disc and it'll be as good as new.

Not sure if that's a good thing or not . . .

It looked like we were getting good penetration but clearly not.