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PDC6000
23rd March 2012, 11:16 AM
Hi All, I am the owner of a 1988 T-Bar which I have had for 3 years, i've visited these forums a few times before when looking for info and found it a great help. I now have a big problem which may be the end of this fantastic car. A few weeks ago when I got home from work sitting on my drive the car just stopped and wouldnt start again (turning over but not firing) turned out the teeth on the timing belt had stripped. I hear it is an interference free engine (is this defintely the case?) so I have replaced the belt and aligned it all up according to the manual yet it still wont start. I have done a compression check and they are all well below what they should be which I think means either there is valve damage or more likely the timing is out(??).
The next step i am looking at is stripping the head and having a look to see if there is any internal damage but i dont want to go to alll that work if there is something simple that i have missed, I would really appreciate some help from someone with a bit of experience on working with these engines

Cheers
Pete

Boondougal
23rd March 2012, 02:11 PM
These engines are definitely non interference so unless the belt failed when you were at max revs then its very unlikely you have any internal damage stopping it from starting so my first port of call would not be stripping it down.


I would revist the belt set up, very easy to get it 180 degrees out if you have never done it before (like me) and i would imagine you may need to look at your dizzy, making sure its set up to fire correctly when No1 is at TDC.

Doh... just seen the compression point.. hmm. What are they supposed to be?

Personally if you have been doing work to the engine i would go over every connection and the timing again, make sure nothing is dilodged, its all connected in the correct order and that the appropriate power id getting to where it needs to be.

Is it cranking? If so it may well be throwing an error code... might want to see if you can read it.

Lastly, fingers crossed someone who knows what they are talking about will be along soon... I am still on a big learning curve with all this. :-)

PDC6000
23rd March 2012, 02:25 PM
Thanks for your response Boondougal, if remember right according to my manual the minimun compression should be 8.5 i think and i'm getting less than that on all of them but like you i am also very much still learning when it comes to car mechanics so have to seek advise from those that do know what they are doing. Ran the diagnostic and got 6 flashes which says this:
" RPM signal. No Ne, G signal (engine revolution sensor) signal to ECU within several seconds after engine is cranked. No Ne, G signal (engine revolution sensor) signal to ECU within several seconds after engine reaches 1,000rpm. "
not 100% sure what that means

bill hulme
23rd March 2012, 03:38 PM
have you had the camshaft pulleys off, if so there are two elongated location slots in each pulley, the location dowel on the inlet should be at 12 o'clock
when the dimple on the pulley is at the top, the exhaust dowel should be at about 25 past, on the other slot, when the camshaft dimple is at top. if you are confused at this you can phone me on 01204 578147
Bill.

PDC6000
23rd March 2012, 04:55 PM
Thanks for your response Bill, not had the camshaft pulleys off so they should be right, and i aligned the timing marks on them up with the marks on the top cam cover and aligned the mark on the crankshaft pulley as well then pulled the belt on over the camshaft pulleys down to the crank pulley

Boondougal
23rd March 2012, 08:20 PM
Have you seen this site? The areas of potential issue are on there.

http://myweb.tiscali.co.uk/jimilawson/Various/ECU%20Codes.html

My bet is a dislodged earth or connection.

jimi
24th March 2012, 02:51 AM
These engines are definitely non interference so unless the belt failed when you were at max revs

The rpm is irrelevant, if the engine is non-interference at 1 rpm then it's non-interference at 7500 rpm :)

PDC6000
24th March 2012, 09:46 AM
Have you seen this site? The areas of potential issue are on there.

http://myweb.tiscali.co.uk/jimilawson/Various/ECU%20Codes.html

My bet is a dislodged earth or connection.

Yeah code 6 is what i've been getting although i dont think this explains the lack of compression, oh and forgot to mention when I did the compression check and was getting low/no results i put a bit of oil in the cylinder and that did improve the results slighlty but still not up to the required minimum of 10.0 that it states in the manual

Sweetpea
25th March 2012, 09:57 PM
Hi Pete,

First off I know almost nothing about these engines. Mine is dead and I haven't yet taken it to bits to fix it. So please feel free to ignore everything I say!
However, if I was in your situation I'd start by checking the cam timing and looking for valve trouble. I reckon if there is no compression it'll never start regardless of what the computer says.

Also, as far as I can see all the timing stuff is in the distributer so you can't get the bottom of the engine out of phase with the top. But I'd like somebody to confirm that or tell me I'm wrong.

So I would...
Take the cam belt covers and the cam covers off. Take all the plugs out. You can now see the belt, cam shafts and the pistons.

Then set No 1 piston to the top. Do this by turning the engine over (with a spanner or socket on the crank pulley) until No 1 piston is at the top. If you can't see it down the plug hole you can CAREFULLY poke a screwdriver down the plug hole and rock the engine until the screwdriver is highest. The timing mark on the crank pulley should be close to the 0 degree mark. If it is you can trust it. Use it to set TDC. If not, oh dear! That's your first problem.

So now, either No 1 or No 4 should be "firing" which means the valves should be closed on one of them. You should be able to slide a feeler gauge between the cam lobes and the followers. If you can't get the feelers under 1 or 4 then the valve timing is definitely wrong. By the same token you shouldn't be able to get a bus through the gap either. If you can you have probably got a stuck or bent valve. You are basically checking the valve clearances at the point the cylinder is firing to make sure both valves are fully closed and not stuck.

If number 1 is "firing" (valves fully closed) number 4 will be at the end of the exhaust stroke / start of the inlet stroke and both valves will be slightly open. You shouldn't be able to get the feeler under any of the lobes

The firing order is apparently 1342 so if you started with 1 and it was ok put half a turn on the crank and check 3. Etc etc...

Finally when you get back to 1 if you take the top off the distributer the rotor arm should be pointing at the number 1 plug lead.

Of course the other thing that causes low compression readings is if the tester hasn't seated in the plug hole properly.

Best of luck
James

superwhite90
26th March 2012, 03:11 PM
You have put the HT leads in the right order haven't you? Sounds silly but this could cause it to not fire.

PDC6000
27th March 2012, 03:52 PM
Thanks for your responses all, all signs are pointing towards some sort of internal damage more than likely valves, piston rings or worn bore or all of the above. think I might be getting rid of it as i cant afford to throw anymore money at it, anyone want a donor car??

Sweetpea
27th March 2012, 10:41 PM
Noooo! Don't give up. Too many are getting broken up as it is.

As I understand it the car was running until the teeth on the cam belt stripped. So we know it's not rings or bores.
If I was a betting man I reckon you'll have got one of the cams a tooth out. You wouldn't be the first or the last.

The error code from the ECU could be an old one and nothing to do with your current problem.

James

PDC6000
30th March 2012, 02:23 PM
Noooo! Don't give up. Too many are getting broken up as it is.

As I understand it the car was running until the teeth on the cam belt stripped. So we know it's not rings or bores.
If I was a betting man I reckon you'll have got one of the cams a tooth out. You wouldn't be the first or the last.

The error code from the ECU could be an old one and nothing to do with your current problem.

James

I really dont want to give up but i also dont have the cash to throw at it. I've been through the procedure again of putting the timing belt on according to the manual and providing the manual is right the belt is on correct, i've also checked to make sure its firring in the right order which it is, and the distributor arm is also in the right place.
To be honest i'm not paying too much attention to the error code from the ECU because as far as i can understand it doesn't explain the lack of compression anyway

pant-era
21st April 2012, 09:39 PM
Where are you located bud?

Deadly_smell
22nd April 2012, 12:13 PM
This looks to me like the crank is 180 degrees out, take the belt off again make sure that the no.1 piston is at TDC using the timing mark and by putting a screw driver or something down the plug hole, then take the rocker covers off and check that when the cams timing marks are lined up that the lobes of the cams are away from the cam followers this will mean that the valves are closed. Put the belt back on check the rotor arm is pointing towards no.1 plug lead and give it a go.

bill hulme
22nd April 2012, 02:24 PM
When you did the compression test did you have the throttle wide open, if you dont do that, there would be very little air going into the cylinders, so you get low compression.
Bill.

bill hulme
22nd April 2012, 03:37 PM
http://www.mr2mk1club.com/images/imported/2012/04/DSC_6758-1.jpg
TDC dimples and camshaft dowel locations on the pulleys left one is the inlet, the right one exhaust, Note the location camshaft pin is in the lower slot
when the pulleys are at TDC.
http://www.mr2mk1club.com/images/imported/2012/04/DSC_6756-1.jpg
There are two marks on the back plate to line the pulleys to.
http://www.mr2mk1club.com/images/imported/2012/04/DSC_6764-1.jpg
On the bottom pulley the left mark is the TDC mark, the one to the right is at 10 degrees for the ignition timing.
http://www.mr2mk1club.com/images/imported/2012/04/DSC_6766-1.jpg
This is how it should look when you fit a new timing belt.
http://www.mr2mk1club.com/images/imported/2012/04/DSC_6792-1.jpg
If you have had the distributer out, leave everthing at TDC, the are two marks to line up,
with the marks lined up slowey slide the distributor back in place.
Bill.

Boondougal
22nd April 2012, 07:09 PM
great pics Bill... really helpfull.

Would be good to get your location mate... someone might be near enough to give it fresh eyes.

Boondougal
23rd April 2012, 09:29 PM
did you get this one sorted?

PDC6000
27th April 2012, 04:00 PM
Hi All apologies for my non response, been a bit busy re-building my bathroom so car has been de-prioritised for the time being. Car is still sat on the drive still in the same condition i'm based in a little Village near Bicester Oxfordshire, my missus keeps moaning at me to take it to the scrappy and get the £150 but i just dont want to see another one go off the road for good and £150 just doesnt seem enough for what could be something simple, If anyone wants it or knows anyone that wants one and has a trailer feel free to make me an offer

Boondougal
27th April 2012, 05:58 PM
Right, i am not that far from you unless you a south side of Bicester and i have just been wrestling with the exact same thing and have just been shown the error of my ways over on IMOC......

If you want i don't mind taking a little trip (not sure 100% when) to see if i can go through the same fault finding that i have done on mine to cover the bases.... admittedly if you look on IMOC i have just shown up my ignorance but TBH i am pretty confident that i could now(and i mean as of 5 mins ago) make sure that nothing mechanical is stopping you from getting it started..

At very least 2 heads might be better than 1

PM and let me know what you think and if you want me to come over send your address and i'll look exactly where you are.