The 90 project

Started by Mat Francis, February 07, 2011, 08:11:14 PM

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festy

I've only read the last few posts in this thread, but I'd suspect a ECU/wiriing instead of blocked injectors.
The injectors are supplied with a constant 12v to one side of their solenoids, and the ECU fires the injectors by grounding the other side for a few milliseconds.
You've confirmed that there's 12v to the injectors - but you mentioned that at no point are they grounded. That is a problem ;)
Does the fuel pump run while you're cranking the engine?
I imagine it primes for a second or two when ignition is switched on, then stops - but does it start again when the engine is turning over?
If not, the ECU might not be getting the rpm signal.
Otherwise if the pump does run, check continuity between the ECU's injector output pin and the injector plug terminal to see if it's a wiring issue, and check if the ECU's injector pin is being grounded while cranking.
You could connect a parker globe to the terminals on one of the injector plugs and see if it flashes while cranking the engine.
If it doesn't, then even sparkling-clean injectors won't help you ;)

Mat Francis

Thanks Festy :)

All of what you have said there is basically in line with my thinking, so fingers crossed the ecu I acquired in my travels this morning will sort it out. Oh and the fuel pump runs while the engine is cranking

Cheers Dehne, I'm using The 2.5 injectors ready. The injector cleaning might be useful, but as Festy points out, I need to get them working  before it is any use.

will report back tonight!
'83 Alfetta Sedan TS
'88 75 3.0
'85 Land Rover County
'87 Land Rover Perentie

dehne

I would be almost certain its blocked injectors, I have some 2nd hand ones if needed, would almost lay money on it
now
1x 85 mdl road 90
2013 Giulietta 1.4
2015 Launch Edition Giulietta
Past
Multiple Alfa 90's, Alfetta's and 147's

Mat Francis

IT RUNS!

Finally got it working after a few more hours dicking around.

As much as I hate to say it, I think in the end it came down to stuck injectors. Tried the new computer first up with no difference at all, and nothing I had was sensitive enough to register injector pulse (don't have a noid light, and the bulb and analogue multi meter didn't work).

Next thing I did was apply 12v directly from the battery to the number 4 injector, to see if it was physically going to work or not. Nothing at first, but then after i touched it a few times it eventually clicked open.

Reconnected the computer, and this time got a brief splutter, as opposed to the absolute nothing I had got everytime before. Took me about an hour and a half to do the same for 4 more injectors (couldn't really be bothered taking the plenum off to get to number 3 to just test a theory I had), but same thing for the rest of them. Nothing at first, but after a few stabs they would eventually open. Gave them a good 30 or so cycles each.

Wired it all back up, and it ran perfectly straight away. Notice how my fuel catch container sits nice and steady :)

http://www.youtube.com/watch?v=lbKJyXtexOQ&context=C45ef2c2ADvjVQa1PpcFMcg2a1wwVpWk5F80JrVCtEvIyP3vmzMrg=

I'm guessing the computer's signal to the injectors simply wasn't strong enough to force them open after they had been sitting for who knows how many years filled with all sorts of crap? If nothing else at least I now have a good understanding of it all and what appears to be a healthy injection system.

Now over the weekend I can tidy up the engine bay, put in all the cooling system and start working on the back end of the car.

Thank you all again for your invaluable input!



'83 Alfetta Sedan TS
'88 75 3.0
'85 Land Rover County
'87 Land Rover Perentie

VeeSix

Where are we Mat, any time for progress recently?  ???
1985 Alfa Romeo GTV6 V6 2.5 12V 
1986 Alfa Romeo 90 V6 2.5 12V
1990 Alfa Romeo 75 V6 3.0 12V Potenziata
1990 Alfa Romeo 164 V6 3.0 12V Zender
1991 Alfa Romeo 164 V6 3.0 12V QV
1992 Alfa Romeo 164 V6 3.0 12V QV

Mat Francis

To the outside world it wouldn't appear that I have really done anything, but yes, I've been at it quite a bit and it is all coming along really well!

As I write this, the gearbox is in the hands of the guru, having a few little tweaks performed on it  ;)

While I have been waiting for this, I have put in the torsion bars, brakes and konis out of the wrecked 75 I got rid of a couple of weeks ago. Still waiting on the new steering rack boots and tie rod ends, but once they are done that is the front end sorted. Took me 3 infuriating tries to get the height right, but I reckon it's looking good.
'83 Alfetta Sedan TS
'88 75 3.0
'85 Land Rover County
'87 Land Rover Perentie

Evan Bottcher

Looking good Mat, in that Alfa 90 rugged-and-handsome-but-definitely-not-pretty kind of way.
Newest to oldest:
'13 Alfa Mito QV
'77 Alfasud Ti
'74 Alfasud Sedan
'68 1750 GTV
--> Slow and Fun - my Alfa journal

Mat Francis

Again not much visually for this as yet, but more progress. I have entered this car in the Broadford sprint in one months time, so no excuses, it is going to be done!

The latest is that I'm halfway through building the back end. As you can see I've put poly bushes all through it- I know there is debate about whether or not this is the way to go, but I'm keen to give it a go and see what I think for myself. New boots on the driveshafts and re packed with grease obviously. I will have the gearbox next week, so I want to be able to drive the thing by the end of next weekend  ;D

In the mean time, I have a question that I think came up a few weeks ago, but can't for the life of me remember the answer or find the thread.

I have two pairs of gearbox mounts, both iso, one from the 90 and one from the 75. The 75 ones have plates welded onto the bottom of them, the 90 ones don't. I assume this is due to the 90 de dion having the spacer block thing welded on, whereas the 75 de dion has removable blocks? Please see attached picture of 90 de dion with the plate from the 75 sitting on it as well.

My best guess is that as I'm using the 75 de dion, I will need to use the 75 gearbox mounts (the ones with the extra plate) on the clutch housing? (or alternatively un pick and re weld the plates onto the 90 mounts). Could someone please explain the relationship between the bits I have here?

Back to it for now to keep going on those pesky little jobs!



'83 Alfetta Sedan TS
'88 75 3.0
'85 Land Rover County
'87 Land Rover Perentie

Mat Francis

Try again with pictures
'83 Alfetta Sedan TS
'88 75 3.0
'85 Land Rover County
'87 Land Rover Perentie

Mat Francis

With time rapidly running out, this weekend saw some solid progress.

Finally got my gearbox Friday afternoon, and with a little more assembly saturday morning this was all sorted. Pictures attached. Can anyone playing at home spot anything different about it?  ;)

Also managed a record time rear pad swap with the poor broken alfetta, so it now has a set of 12 lap old ebc reds in the back. Should do the trick.

'83 Alfetta Sedan TS
'88 75 3.0
'85 Land Rover County
'87 Land Rover Perentie

Mat Francis

I then assembled the de dion on the ground, without a hoist I have found this to be the easiest way to do things in the past, and wasn't going to experiment with anything new this time round. The old man was a big help yesterday afternoon, with two people on it this took no time at all.

A few frothies last night saw a later start than I would of liked today, however I'm still pretty happy with where it is at considering. Further down you can see my delicate balancing act of putting the whole lot in on my own. Not sure if I was just lucky or I'm getting the hang of it, but it hardly wrestled me, and everything lined up nicely.
'83 Alfetta Sedan TS
'88 75 3.0
'85 Land Rover County
'87 Land Rover Perentie

Mat Francis

Once everything was in position, but before it was all done up, i dropped the car down onto the ground, and once again my luck seemed to continue! Ride height was perfect, which I was absolutely stoked with.

Hooked everything up except the gear linkage, couldn't quite get the roll pin hole lined up, and i was too tired and frustrated to fight it by this stage. During the week I'll finish that and a few other little bits and pieces, and with any luck I should be able to drive it up the street for it's first self powered voyage in over a decade!
'83 Alfetta Sedan TS
'88 75 3.0
'85 Land Rover County
'87 Land Rover Perentie

Frank Musco

Well Done!

You've obviously done it too many times now. Nice balancing act with the correct blocks of wood. You could probably do it with one hand tied behind your back.

Quote from: Mat Francis on June 24, 2012, 09:01:32 PM
Can anyone playing at home spot anything different about it?  ;)
Its been a few years I've played with those gearboxs, and it 'appears' right, but looks are often deceptive...so is it something to do with number of teeth?  ;)

scott.venables

Nice work Matt!

Is the weirdness the gear for a cable drive speedo instead of the electronic?

Mat Francis

Quote from: scott.venables on June 25, 2012, 12:25:09 AM

Is the weirdness the gear for a cable drive speedo instead of the electronic?

Quote from: Frank Musco on June 24, 2012, 09:52:48 PM

Its been a few years I've played with those gearboxs, and it 'appears' right, but looks are often deceptive...so is it something to do with number of teeth?  ;)

Aha! Can't get anything past you blokes. Well spotted. It started life as a 3L 75 gearbox, but it now has a 4.3 crownwheel and pinion in it, hence the older style speedo drive. Also had the LSD shimmed up while it was out, not that there's any way of spotting that. Should get up and move nicely  ;D

In regards to the roll pin, good tip, thank you. I actually couldn't get the holes lined up yet though, so off it comes and i'll lightly emery paper the lot then try again.
'83 Alfetta Sedan TS
'88 75 3.0
'85 Land Rover County
'87 Land Rover Perentie