UPDATE2 Replaced Engine - now feels GREAT!!!!

Post by **mikey9** » 20 Sep 2008, 21:22

OK, the story.
1.9DG (1990) 88k miles - water jacket failure - engine dropped replaced by 1,9DG 20k VW recon from pick up I drove before it was dropped out - ran well - accelerated smoothy - hit 70 easily (well...). no leaks etc. *DG....code.

Now this engine was a replacement for the orig DF in the 1984 pick up so came with early water pump/thermostat and exhaust and a different carb. This has all been stripped off and replaced by:

Water Pump (new 2 months ago from my dead DG)
Carb (and LPG fittings from my van)
New Exhaust

Otherwise we have the replacement engine installed in my 1990 Hi Top.

After some coolant bleeding issues - and an air filter to carb big rubber pipe not being jubileed on- we are now running smoothly - initally on petrol - but now back on LPG.

The problem (if you have stayed with me so far...thanks)....it feels like I am down about 10bhp.
Now I don't expect fireworks - I have done 10k on a LPG DG and know it's limitations - but this new one really does feel slow (unlike when it was in the pick up - (I know the pick up isn't a high top - or a camper but....still).

To give you an idea - we did 100 miles in it today (on LPG). Ran well however I timed 0-50 at over 35 secs and there wasn't any point in looking at a 60mph time as we weren't getting there unless there was a downhill....It ran well but took forever to get up to a decent speed - then there was no real power availbale to get back up to speed if you slowed down. Only from rest does it feel like the old motor.

I know about the power valve etc and am happy fettling for optimium running - but the sluggishness is similar on petrol.....this feels like something else we have missed. Almost like the engine is spinning and running very sweetly just the final effect of forward propulsion is lacking - I find myself leaning forward to make it go faster - and clenching when I pull out of junctions......

I have replaced sparks (set to 50thou) today, and air filter (no difference). Has fresh Oil and filter.

I was wondering if the dizzy could have this kind of power reducing effect - is there any difference between early and late?. We currently have my cap and leads (new) on the old engine dizzy with a rev limiting rotor arm.

Sorry about the ramble....tis getting late and I have been surfing threads for inspiration for far too long. If we could get that extra 10bhp back I would be happy.

Post by **HarryMann** » 20 Sep 2008, 21:43

engine dropped replaced by 1,9DG 20k VW recon

Genuine VW recon, done 20,000 since recon ??

Sure its a DG not DF?

How coud it have early dizzie if yours was 1990, surely that's late?

Sure you have the advance retard timed up properly, how did you check the centr. advance and vac adv/ret working OK and then get it timed up (static setting or strobed it), if so to what figures.

Does it pink (on petrol)?

Post by **Ian Hulley** » 20 Sep 2008, 22:01

Check it hasn't got a stooopid restricted rotor arm, they cut the revs off at 3,000 or similar

Ian

Which part of ^^^^ didn't you get ? Put a standard rotor arm in ... the max power on a DG is (allegedly) at 3,800 rpm ... i.e. 800 rpm AFTER your "pooh" one shorts out.

Ian.

Post by **mikey9** » 21 Sep 2008, 06:01

Harry.

Genuine VW recon, done 20,000 since recon ??

Yes

Sure its a DG not DF?

Not sure how to tell beyond the big *DG number stamped on the block tower?

How coud it have early dizzie if yours was 1990, surely that's late?

Sorry, I meant it has the dizzie from the replacement engine (i.e. we haven't replaced the dizzie with the one from my late engine). I was wondering if, when the engine was fitted to the doner vehicel - they had reused the dizzy from it's dead engine - making it a 1984 model as fitted to a DF? Is there someway I can identify such a dizzy - and would this cause this kind of probs?

Sure you have the advance retard timed up properly, how did you check the centr. advance and vac adv/ret working OK and then get it timed up (static setting or strobed it), if so to what figures.

(now bear with me here - we are stretching my jiffy bag of expertese...)
No - left the garage to that bit - 5 degrees as in the haynes - although he did vary up to 7deg to just pinking but set it back to 5 I think - but having read a fair bit on here - I get the impression it can be different for each engine - as for the vac advance and retard - I will have a search on here for how to test if it's working (relied on the garage for set up - they are good honest - but admit they don't do many wbx's....not a lot of demand up here!)

Does it pink (on petrol)?

No - see above

Ian,

Check it hasn't got a stooopid restricted rotor arm, they cut the revs off at 3,000 or similar Confused

Hmmm - that was where I was hoping the prob is.....it has got one of them rev limiting ones - not sure what it cuts in at - do they stick? Is there a 3000rev restricter one? Will check tomorrow when I pick up all the bits of my engine and will swap over rotors (I think I had an unrestricted one on).

Post by **steve8090** » 21 Sep 2008, 06:45

I have replaced sparks (set to 50thou) today, and air filter (no difference). Has fresh Oil and filter

Gap is far too big, you will have a very weak spark at that, should be 25thou max

Post by **Ian Hulley** » 21 Sep 2008, 09:00

Ditch the restricted rotor arm and reset the plugs (as the Maestro says)

Ian.

Post by **mikey9** » 21 Sep 2008, 13:21

Ok, I have been to borrow a mates identical (1.9DG Autosleeper Trident Hitop). Nicked his rotor arm (still a rev limited one) - put into ours - drove a set local hilly route - mental note of speeds, gear changes etc.

Then put ours back in and did the same
No difference found.

Then did it in his van with his rotor arm back in it. Just felt like my old engine (not surprisingly).

In mine I was 5 -10 mph down and had to back off at bends where I could keep foot in in ours. Clearly a different feel/speed but only really noticable beyond 30 MPH ish. Both are similar at lower speeds.

Next to reset the spark gap as per the maestro's advice.

So we are back to timing and/or vac advance.....

Post by **mikey9** » 21 Sep 2008, 13:23

....oh and I just filled up with LPG after 134 miles (42 litres) so we were only getting approx 15mpg on yesterdays run (I turned the power valve up a bit to compensate for the lack of power).

Post by **steve8090** » 21 Sep 2008, 14:38

Also check that the DF inlet manifold gaskets havn't found their way onto your van, the inlet gaskets are roughly half the size of the DG ones and do restrict the flow of petrol / gas mixture.

Post by **mikey9** » 21 Sep 2008, 15:10

Got new DG Manifold gaskets and put my manifold off my DG (plus its carb) (I say "I" did, I mean my garage did - but I got the them the bits from VW garage).

I have checked and they match the diagram at:
http://www.vagcat.com/epc/cat/vw/T2/1990/78/49/881948/
and are mounted as shown.

Another thought - can you identify heads (as DG or DF) using the number stamped on one of them (I have 025101375 on the LH head). VAGCAT lists 025101355B as DG cylinder head complete.....?

Website · Post by **syncrosimon** » 21 Sep 2008, 17:30

Put the van on a rolling road, then you will know for sure what is happening, (my bus feels slow sometimes, dont know if it is a headwind, or a gradient or what, and sometimes she feels quite nippy). The rolling road will show up any problems, and if it is not right, they will tell you why it is not right.
After my birthday treat of a rolling road tune, my DJ feels really really nice, did cost 80 quid, but you can spend that in the garage replacing un necessary parts in the blink of an eye.
I am without a shadow of a doubt gonna do the rolling road tune once a year, and not touch it in between.

Post by **mikey9** » 21 Sep 2008, 19:32

Just checked what I wrote -abou the spark gaps - these are set to 0.5mm NOT 50thou.....

When will we all go metric - I can't get the hang of this imperial thing.......

Post by **HarryMann** » 21 Sep 2008, 20:12

When will we all go metric - I can't get the hang of this imperial thing.......

Hehe, Imperial was around several thousand years before metric...

.5mm =~ 20 thou

Post by **mikey9** » 22 Sep 2008, 20:56

OK,
I have my old engine and bits back now.

I have identified that the old carb on the replacement engine was a PICT 34
[IMG:640:480]http://i281.photobucket.com/albums/kk21 ... Engine.jpg[/img]

WIthout taking off my manifold that is on the engine now installed I don't think I can confirm whether the replacement has DF or DG heads (making it a DF or a DG) however - from the old inlet manifold I have taken the following:

With gasket on (DG size holes I guess on the gasket)
[IMG:640:480]http://i281.photobucket.com/albums/kk21 ... gasket.jpg[/img]

Surfaces appear to show a bigger hole on the heads than that in the manifold......
[IMG:640:480]http://i281.photobucket.com/albums/kk21 ... Engine.jpg[/img]

.............................

Garage confirmed to me he set timing to 5 degrees BTDC

I have had a suck on the vacuum tube going into the dizzy (it is my original dizzy from my DG) to see if I could make the dizzy advance. I could hear a "gloop/sloop" sound but nothing moved - should it have ??? or is the movement somewhere buried in the dizzy......?

.............................

Ian - I now have a non limited rotor arm back - will drop that in tomorrow - otherwise off to borrow a strobe and a mate who knows more than me -

Post by **mikey9** » 23 Sep 2008, 15:13

I have now tried an unlimited rotor arm - no difference noticeable.
-------------------------

I then tried driving the van - then stopped and disconnected the vacuum tube between carb and dizzy (assuming that if I disconnect the pipe and drive - and it runs the same - then I have located my problem - or one of them....!)

......and performance was very similar. No pinking noticeable and very little performance difference - a bit quicker 0-30 with it connected - after that no difference......

I found a flat bit and did a 30-40 acceleration in 3rd (a couple of times eac)

Connected Vacuum = 9 secs
Disconnected = 7 secs
(bit weird - I wasn't expecting it to be slower connected up?)

There is a bit of vaccuum as when i disconnect the tube at the carb - there is a "sloooook" sound - of course I guess there will be a vacuum at that end - my issue (I think) is at the dizzy end. the revs also drob at idle when I disconnect the tube...

So my latest thinking (pleeeeease contradict/correct me if I am guessing wrong or making things up) is that there is either:

1. A leak in the tube from Carb to Vacuum (will have a play later with air and a bowl of water) and then renew all the hose bits on it.

2. A failed/failing diaphragm attached to the dizzy

3. Something further down the dizzy - like sticking weights etc..

4. Something completely different ..........like DF heads