SAAB V4 Forum
SAAB V4 Forum
Home | Profile | Register | Active Topics | Members | Search | FAQ
Username:
Password:
Save Password
Forgot your Password?

 All Forums
 Technical
 Tuning
 How to tune the V4?
 New Topic  Reply to Topic 
 Printer Friendly 
Next Page
AuthorPrevious Topic Topic Next Topic
Page  of 2

UK_Sub
V4 Guru

United Kingdom
2555 Posts

Posted - 03 Dec 2007 :  09:40:40 Show Profile Reply with Quote
I managed to source and fit a replacement engine at the weekend. We eventually got it running, it's a bit 'tappety' - but I can sort that later . . .

I just wanted to know how to check everything is setup in the correct position - ie: pulley in TDC, which spark plug the rotor arm should be point too etc?

It's just that she runs a bit lumpy, especially when cold.

Any help/wisdom would be gratefully received!

Simon

ps: I assume all the info will be in the Haynes book - I just don't have one with me!?!

Edited by - UK_Sub on 03 Dec 2007 10:50:36

UK_Sub
V4 Guru

United Kingdom
2555 Posts

Posted - 03 Dec 2007 :  12:30:40 Show Profile Reply with Quote
Basically I think I need to know . .

If the bottom pulley is at TDC - which plug should the rotor arm be pointing at. Also, how do you tell if the engine is on the compression or exhaust stroke - assuming the timing needs to set for the compression stroke?
Go to Top of Page

jdt
V4 Fanatic

United Kingdom
340 Posts

Posted - 03 Dec 2007 :  15:18:13 Show Profile Reply with Quote
To find out compression stroke put your finger over the plug hole and turn engine over - but orientation of leads in cap does not really matter just confusing when you read the manual. As your car runs the order must be correct

Set the timing with a strobe light (low tickover and vacumn advance pipe off)check plugs and points gap

You need to adjust the tappets cannot remember off the top of my head the clearances or procedure but must be correct

If you turn idle mixture screw on car to give highest revs you will be close to ideal

Is auto choke functioning correctly?
Go to Top of Page

UK_Sub
V4 Guru

United Kingdom
2555 Posts

Posted - 03 Dec 2007 :  16:04:26 Show Profile Reply with Quote
Thanks for the tips.

The plug on no.1 cylinder is really awkwardly placed - do you HAVE to remove the alternator to get at it?

The tappets are very noisy on one side - I'll refer to the manual to see what the gap/procedure should be.

I don't think the auto-choke is working properly - I tried to find a pic of how the pipes are supposed to connect (at the moment the hose coming from the front end is attached to the upper connection on the auto-choke - is that right?). Water will come out of the drain tap - but only under high revs. I took the water pump apart and it looks brand new.

When I swapped the carb over, I cleverly turned it upside down - so there may be a blockage - but it is getting fuel.

At the moment - she stalls when I come to a halt, even though I've raised the revs by turning in the mixture screw.

Maybe the engine is still tight, not having been run for a few years - she doesn't have the same 'go' that my last engine had - struggling up hills etc.

Sorry for all the waffling - thought all the history might help
Go to Top of Page

Kooda
V4 Fanatic

United Kingdom
250 Posts

Posted - 03 Dec 2007 :  17:32:05 Show Profile Reply with Quote
You dont have to take the altinator off, but it is much, much easier if you do.

I cant help you with the FoMoCo carb set up as mine got scrapped a long time ago. Most carbs will have an idle mixture screw and a idle speed screw. I set the idle by fiddling with the mixture until the revs are as high as they will go. Then adjust the revs back down to 8-900 rpm using the idle speed screw.

Setting the tappets will help the power a little as it sharpens up the valve timing.

Have you checked the compression?
Go to Top of Page

jdt
V4 Fanatic

United Kingdom
340 Posts

Posted - 03 Dec 2007 :  19:36:06 Show Profile Reply with Quote
You can remove no 1 plug without touching the alternator

I use a plug socket (from a socket set) that has a hex at the top and use a spanner on the hex rather than a ratchet

hope that poor descrioption makes sense but it works well
Go to Top of Page

James Ranaldi
V4 Guru

United Kingdom
1475 Posts

Posted - 03 Dec 2007 :  20:11:35 Show Profile Reply with Quote
Nice one JDT...hadn't thought of that!!

The SAAB V4 toolkit ( if you have any left!) should have a funny little plug spanner with an off-set head which is specially designed to allow for the removal of No.1 plug without touching the Alternator.

Glad you are up and running again UK_SUB.

Cheers,
James

Thrummmm....Thrummmm
Go to Top of Page

Woody
V4 Guru

United Kingdom
2758 Posts

Posted - 03 Dec 2007 :  20:13:00 Show Profile Reply with Quote
As you say you need to do the tappets, whip the rocker covers off and rotate the engine. When the pulley mark approaches TDC, it is TDC on no 1 if the rockers on that cylinder are stationery. You will find that those for No4 are rocking. Clearances (cold) are Inlet: 0.014in(0.35mm) and Exhaust: 0.016in(0.40mm). Adjust the clearance so there is just a perceptible drag on the feeler gauges. Do a visual check to ensure that the tappet surfaces are not worn or else you will get incorrect adjustment. Continue to rotate and do the pairs for 3, 4 and two respectively. Continue to rotate and double check your clearances. Then you can do a visual check on your timing. Basic is 9degrees BTDC on a single carb. I have not used a strobe light on a V4 for such a long time and then it was on fully leaded, so cannot comment on the same for unleaded.
I would not have thought your water pipe orientation is important as the connections are to use the heat temperature from the water to cause the bi-metal spring in the housing to expand then wind back on it self to cause the upper choke butterfly to open. There is a counterweight inside the housing which can get stuck which results in improper operation. Ensure that the butterfly and the connecting links are lubricated and free.
A tachometer is really useful to get the idle correct. You will get a good feeling when it is done and you will find the engine starts instantly.
Go to Top of Page

UK_Sub
V4 Guru

United Kingdom
2555 Posts

Posted - 04 Dec 2007 :  10:18:01 Show Profile Reply with Quote
Cheers fellas,

I appreciate all the help - refering to the Manual is often confusing and frustrating - so I really appreciate all the info - I will have another go at it tonight.

Thanks to jdt too - a nice bit of common sense - I've even got the tool James mentioned - so I've got no excuses
Go to Top of Page

Derek
V4 Guru

United Kingdom
2187 Posts

Posted - 04 Dec 2007 :  12:25:33 Show Profile Reply with Quote
I got this advice from Chip Lamb when I enquired on Yahoo VSAAB
"I usually run about .032" plug gap and 6 deg BTDC static timing. Simply get the pulley on TDC #1, then rotate to 6BTDC, then set the mark on the distributor body in line with the "nose" on the rotor.
Running .028" plug gap (standard) is fine but the slightly wider gap
gives a little better idle on the average V4 with Pertronix/Blue Coil."
The extra plug gap seemed to work for me with Pertronix/Blue Coil.
My distributor clamp/block has a narrow punch mark plus a splash of blue paint which was obviously there to "seal" the setting. It seems about right and as 1º of dizzy is 2º of timing is very sensitive to change (clockwise retards). Advance retard system needs to be loose and well lubricated. A few drops of oil on the felt pad under the rotor useful and often forgotten.

Go to Top of Page

UK_Sub
V4 Guru

United Kingdom
2555 Posts

Posted - 04 Dec 2007 :  21:39:26 Show Profile Reply with Quote
Adjusted the tappets and wow - what a difference!!! he revs smoothly and pulls along really nicely, I no longer have to drop down to 2nd to go up hills!

She still sounds a bit rattley at the top end, not sure if it's the tappets - could it be pinking? I didn't adjust the position of the dizzy - but at 6 degrees off TDC - the rotor arm was pointing right at the mark on the dizzy - so I figured its in the right place?

The auto-choke still isn't working - I took it apart and blew into it - air came out the other end, so I'm guessing it's not blocked.

She still needs some fine tuning, but I can hopefully get it all sorted - for now, I'm over the moon!

Thanks again for all your advice
Go to Top of Page

James Ayres
V4 Mad

United Kingdom
652 Posts

Posted - 04 Dec 2007 :  21:59:19 Show Profile Reply with Quote
Just continue to tweak the timing bit by bit and you'll have it running fine in no time. After I fitted a new engine I set mine as recommended and it ran like a bag of spanners, a few tweaks over a few days and a few carb adjustments and she now runs better than ever! Just be patient and make sure you take her for a few long runs as well, it helps to 'settle' things down.

Keep on thrumming
Go to Top of Page

freewheeler
V4 Mad

United Kingdom
601 Posts

Posted - 05 Dec 2007 :  22:28:41 Show Profile Reply with Quote
My lovingly rebuilt engine is in my garage, still sitting on its frame waiting for me to finish with the engine bay and suspension etc...
I cant wait to get it back into the car and fired up. Fingers crossed everything will be ok, but you never know. It is so rewarding just to spend hours and hours fine tuning everything.

James is right.

UK sub. It is great to know that you have it running well.

--------------------------------------------------------------------------------

http://www.lihikset.net/images/kuuppa/index.htm


http://www.saabphotos.com/gallery/My-other-saabs


Go to Top of Page

UK_Sub
V4 Guru

United Kingdom
2555 Posts

Posted - 11 Dec 2007 :  13:40:13 Show Profile Reply with Quote
Just a quick update . . .

Car went into my local auto-electrician for a tune - seems I was 2 degrees (advanced) out on my timing, but otherwise OK. I got him to do a compression test too - No.1 cylinder 11bar - No.s 2 & 3 10bar - No.4 was only 6 bar though! This could be the valve stems - so I will do another cold-test, to see if there's any difference.

The auto-choke worked for the first time today (well, eventually, after about 5 miles). When you bleed the system, where should the heater controls be? - it just says 'fully open' in the manual, but nothing happened when all the levers were up (which I assumed was fully open), or have I got it wrong?

Cheers,

Simon
Go to Top of Page

Mr Burrrrrrrrrrt
V4 Fanatic

United Kingdom
344 Posts

Posted - 11 Dec 2007 :  14:47:00 Show Profile Reply with Quote
Fully open as in heater fully on so water circulates freely. Give it a bit of a rev periodically when bleeding.
Go to Top of Page

Kooda
V4 Fanatic

United Kingdom
250 Posts

Posted - 11 Dec 2007 :  18:20:56 Show Profile Reply with Quote
check that valve on the front of the heater box. I spent ages tring to sort mine only to realise that the cable wasn't attached to the valve, which remained closed.
Go to Top of Page
Page  of 2Previous Topic Topic Next Topic 
Next Page
 New Topic  Reply to Topic 
 Printer Friendly 
Jump To: 
Snitz Forums 2000
SAAB V4 Forum© 2000-04 Snitz CommunicationsGo To Top Of Page