Timing and misfire 1988 gti on carbs

I've had a real head scratcher today.

Not had my golf long and put a few posts up about it. Overbored to 1900 running bike carbs but the basic install looks sound.

It has been running like a dog, misfirng and spluttering ever since I bought it but the engine wasn't the selling point, I was thinking 1.8t BAM route but the bike carbed DX does appeal.

The traditionalist side of me isn't that bothered about the speed as I've got other cars to go fast in so I'd rather have something simple to tinker with, today I decided to reset the timing as per the handy guides on here.

To start with I got the crank and fly to TDC, all good but the dizzy and cam were way out  as below



So I followed the guide on here, dropped the cambelt and moved the cam back to what should be TDC as per the plastic mark on the cam cover. I also took the dizzy off and realigned it all perfect.

Good job done I thought. All back together, turned the engine over by hand and it seemed good.

Tried to start, sounded really dodgy and unwell when cranking and absolutely no chance of firing.

Took it all apart twice and then decided to put it back as I had found it.

Another 30 mins of cranking and exhaust back fires and carb back fires, I started moving the dizzy about and the leads around the cap in the 1 3 4 2 order and eventually got it running to move into the garage.

Still misfiring and running rough on what's supposed to be a newly rebuilt engine with zero miles on it.

Question is, should the cam timing mark be so far out to let it run?? I've got a horrible feeling the timing isn't the issue and it's bent/sticking valve on cyld 1.

I'm half tempted to take the head off and inspect further. Plug 1 is all black compared to brown of the other three and there is Mayo under the oil cap but the hopeful side of me thought that might be because the car hasn't been driven but logic is saying otherwise

It's possible the pulley is on backwards. Have a look on the other side. See if you can see a line instead of a dot. It might have the lettering T-O next to it.

Will do, cheers Steve.

It's definitely got a dot on the side it's on at present. 

When I took the belt off and put the spanner/socket on it, the pulley naturally fell forward to the 2 o'clock position as though it dropped off the cam lobe and the valves were shut.

The more I've been thinking about things last night though, I'm thinking the head gasket has gone around cylinder 1 with the black spark plug, smoking exhaust and Mayo under the cap. Bit frustrating because the engine has only recently been built I think.

Just got to track down a new one suitable for the 1900 conversion.

Ah well, I wanted a project!

I meant to say, I am just going to try a different plug lead today on cyld 1 just to rule that out before I strip the engine down.

All fun and games though 

Lets get the timing marks down.
on a 88 that is a 1.8
Finger on the tranny to the 0 mark on the fly wheel, if you are on the diamond hash, then that is the 6btdc mark as some manufacturers only cut the diamond and don't stamp the (O) marks on the flywheel or Pressure plate.
see the difference:


The Cam isn't at the 0|t mark on the front of the engine as that looks to be a 90ish 1.8 Digi Cam gear, but there is a dimple on the mack side of the cam that has to be even with the valve cover tin, and not the rebar.

90s digi


88 CIS



The dizzy is set so that the has in the Diz is sitting at the 12, to 12:30 position, and that the rotor is in the middle of the stamped hash by rotating the intermediate gear after the belt is loosened. Any other position of the basic diz when it isn't at the 12-12:30 position is not going to give you the adjustment that you may need to make with a timing light.



The diz with the rotor at the shown position is where the number 1 plug lead goes to.
The wires follow 1-3-4-2



Using ngk plugs makes the car run a tad better, as my digifants seemed to run better on them.

I have had a time diagnosing the cruddy running digi I had because my new set of Bosch triple plats had one bad plug in the set, compounded by a bad spark wire (HV lead) on the original set, my replacement set of Bosch had 2 bad plugs in it, and with the Original bad lead still ont he car, I had 3 bad plugs…. The Saving grace for me was my 2nd Cabby which was running fine, I swapped the cap and plugs over and found it ran great.

When I pulled the new set of plugs out I found that 2 had no signs of operation and smelled of raw gas.  So I switched to NGK, and all my new plugs worked, when I placed my original cap and wires on, I had a stumble, swapping out the wires I found that I had 1 bad wire….

I then used my DVOM and measures the resistance of all the BOSCH plugs (triple Plat) and found that I had 3 that had infinite resistance.
The wire in question also showed infinite resistance.  So don't assume you have a bad wire, take out your DVOM and measure the resistance of them…the wires and the plugs.

Be-sure that you set the timing to my suggestions as well.

If you set the finger to the diamond then your static timing is set to 6BTDC not 0.
and that can be a little off….

just my 2 cents on the pictures that I am looking at that you provided.

My photos are from www.cabby-info.com and Thanks to Kammy's wonderful site.

Thanks Brian,

I'd definitely lined the Crank and fly TDC up correctly, i followed the guide to the letter. Its possibly the cam gear that is throwing me.

I'm dragging it out the garage again shortly to lose more hours of family time so will check the back of the cam gear.

I've checked my compression today and whilst it's low, they are all within 10 percent of each other so it's got to be the cam timing that's out and the valves aren't fully shutting. Having looked at the pulley i think it's on backwards.





I'm reading horror stories about how hard it is to get the pulley off to flip it over. My next door neighbour has a makita impact driver he can lend me, will this be enough to loosen the bolt or does it need air? 

He also has full airline and tools but I can't really move my car to his garage very easily, not sure how portable his compressor is.

Loosen the belt.
Loosen the bolt on the pulley about 3 turns
Use a 3 finger pulley remover on the bolt head as the fulcrum.  Easy peasy, as you tighten the puller and it is taking strain tap (I said TAP) the rear of the pulley and it may come off really really easy.

That plastic guard with the timing marks on should not be on a 1988 DX engine and you use the top of the head as Briano1234 mentioned above to check the timing. It might be someone has fitted it to stop the cables catching on the cambelt cog as they have removed the top of the metal cambelt cover?

Might be worth removing the cam cover and see where the cam shaft is, on cylinder 1 the 2 cam lobs should be pointing up when it's all timed up to DTC.

To remove the bolt on the cambelt cog I use a bit of wood along the head to protect it and a metal bar from my trolly Jack in one of the holes and onto the wood to stop it moving when undoing the bolt with a standard socket set.

so this is a dx basic 8v engine ?

Thanks again for the replies, it's things like the plastic cambelt cover that are throwing me. It's a real mishmash of parts and I'm stumbling through.

Hopefully I'll get there with this engine with all the valves intact when I do finally get it timed up.

I might get lucky and the cam pulley will come off easy as it's done no miles since being built (or so I believe).

I'll pull the cam cover too and check the lobe positions, good shout

get rid off the cosmetics they do not really contribute
to anything camshaft pulley is on a woodruff key not
an heartache will come straight of why do do you want
the pulley off in the first place

The pulley has been fitted back to front from what I can see. Just a dot on the outer face which I think should be on the inner side nearest the engine?

I'm learning as I go, only ever stripped KR 16valves before so will stand corrected

pulley

I can't remember the marks on a pulley each side, but how far out are you thinking it is?

Its pretty easy to just look at the cam and see if its grossly out, by where the lobes are - at TDC you'd expect  the lobes to be clear of the valves, so both are closed.

Nicci Paul, just stood looking at my pulley in the garage, it’s like yours and can’t technically go on any other way can it?

It would be offset it it was flipped.

Just checked TDC on crank and fly

This is where the fly is

 And this is where the cam pulley currently is

I don’t know how it’s even running to be honest if it is this far out.

So as I understand it now, if I slacken the belt and move the yellow dot to line through with the slit where my thumb is, those valves should then be where they need to be.

I will take the cam cover off as well to check all of that


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Sorry I know I need to move the fly to 6degree Mark as well.

I’m doing that before I touch the belt etc


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So, fly to 6 degree before TDC, cam dot lining through with the mark?

I could just feel the start of resistance on the cam pulley as I turned it forwards.

I’ll pull the cam cover tomorrow and check that, set the dizzy and that should be right?


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There is dots on both sides of the cog, so don't line it up with the one you can see in your picture as that's the wrong side if it's an original head from a 1988 car.


See if you can see anything on the inside of the cog.

Have a look at these pictures of my 1988 car.
View topic: Help confused- Timing marks - The Mk1 Golf Owners Club

So, fly to 6 degree before TDC, cam dot lining through with the mark?

I could just feel the start of resistance on the cam pulley as I turned it forwards.

I’ll pull the cam cover tomorrow and check that, set the dizzy and that should be right?


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