Replacement engine

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alexperkins
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Re: Replacement engine

Post by alexperkins » Fri Jan 05, 2018 4:17 pm

A decent mechanic would take no more than an hour to diagnose and correct the timing.

You should be able to do it yourself. Simple check the timing as per that diagram and the steps noted, and see how its looking. Then its just a case of slackening the tensioner, removing the belt, correcting the cam(s) putting the belt back on and tightening the tensioner back up.

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Re: Replacement engine

Post by littlepolo » Fri Jan 05, 2018 4:23 pm

The irony is I did its first belt swap using a meccano set (OK, some scrap metal and bolts) to set the cams/timing.

This time around I got the proper tool and messed it up.

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Re: Replacement engine

Post by alexperkins » Fri Jan 05, 2018 4:24 pm

Its easily done. It doesnt take much to get it out. If the tensioner isnt right, it can go out of timing after a few revolutions

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Re: Replacement engine

Post by RUM4MO » Fri Jan 05, 2018 6:48 pm

Ah, sounds like the end could be in sight! A month or so ago, I was helping my mate get his old SAAB 96 which has a German Ford 1.5 V4 in it back running after getting lead free tolerant valve seats fitted and a bent push rod replaced, it just would not run and kept sending flames back out the carb inlet. After nearly discharging the battery fully, we called it a night and out the battery on charge and cracked open some whisky wine and food! Next day with a charged battery so no luck, then I switched my brain on and went over what work he had done prior to me arriving - the distributor was fitted 180 degrees out, changing that sorted things out very nicely! It tends to be just too easy to ignore checking some basic things once you have your blinkers on, very difficult to stand back and think about all the possibilities.

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Re: Replacement engine

Post by littlepolo » Sat Jan 06, 2018 3:59 pm

After checking the timing today it looks like the valve timing is late (No 1 cylinder is after the TDC timing mark when the locking tool drops into the cam sprockets. It looks like it is a tooth out. If I'm not mistaken the sprocket is 24 teeth and 360/24 equates to 15 degrees. With the valve timing retarded by this amount is there any risk of a bent valve?

The main cambelt is new-ish (less than 5 miles use) and the tensioner only a few thousand miles (less than 12 months). Are these OK to refit?

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Re: Replacement engine

Post by alexperkins » Sat Jan 06, 2018 4:03 pm

A tooth out won’t damage the valves

And yes, you can reuse everything no problem

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Re: Replacement engine

Post by littlepolo » Mon Jan 08, 2018 4:43 pm

Stripped down and checked the timing belts vs. the indexes. Found the crank pulley was advanced one tooth meaning the valve timing was retarded. Also found the camshaft link belt was out as the locking tool would not go in both holes at TDC at the same time. It looks like the exhaust was retarded a further tooth. Thinking back it had been quite an effort to get the belt on and that might have been because the index was out.

Reset the camshaft link belt ensuring the locking tool went in to both sprockets correctly then proceeded to reset the main timing belt accordingly. With the camshaft link belt correctly indexed the main timing belt went on quite easily (and easier than before). Rotated two full revolutions and it was clear the timing was correct (easy to drop in the locking tool and remove it).

Did a quick startup to check the running condition and the engine started first time. Definitely running better with the correct timing. One thing I did notice was quite a lot of noise from the end of the cylinder head nearest the belts. When I had started it up before there was light tappet noise and it settled down fairly quickly to normal levels of noise for a VW engine. Would the changed (correct) timing be an explanation for this - as in some of the hydraulic tappets have maybe not yet pumped up properly? Ran out of time today but will take it out for a run tomorrow to see if it settles down when warmed up.

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Re: Replacement engine

Post by alexperkins » Mon Jan 08, 2018 4:48 pm

Thats good youve managed to get the timing sorted

Sometimes, if the timing has been out, it can take a few mins for it to settle down. Especially if its cold, as the oil is thicker and the journals take a few mins to fill properly.

When i did the HG on my Mk2 GTI it sounded like a bag of nails as the head was empty of oil (even though I primed it a fair amount whilst rebuilding it and before i put the cam cover back on). After 10 mins it sounded sweet as a nut

Run it for 5-10 mins and see how its going.

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Re: Replacement engine

Post by littlepolo » Tue Jan 09, 2018 11:54 am

Test driven this morning after clearing codes. All seems to be OK. Quieter than it has ever been.

I'll put up some photos and a summary later.

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Re: Replacement engine

Post by alexperkins » Tue Jan 09, 2018 11:56 am

Im glad we managed to get it resolved. On the flip side, you've plenty of new parts now that will keep it running better for longer 8)

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Re: Replacement engine

Post by littlepolo » Tue Jan 09, 2018 1:23 pm

Spoke a bit too soon. After a lengthy test drive it started to run rough when I came to a halt.

It ran perfectly well at highway speeds (60mph).

DTC 17961 & 17912. Going to switch the MAP sensor.

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Re: Replacement engine

Post by alexperkins » Tue Jan 09, 2018 1:29 pm

VAG Error Code: 17961
EOBD II Error Code: P1553

Fault Location:
Manifold Absolute Pressure (MAP) Sensor (G71)/Barometric Pressure (BARO) Sensor (F96) - Range/Performance Problem

Possible Cause:
Intake/exhaust leak.
Exhaust Gas Recirculation (EGR) system.
Evaporative Emission (EVAP) Canister Purge Valve (N80).
Throttle control unit.
Wiring.
Manifold Absolute Pressure (MAP) Sensor (G71).
Barometric Pressure (BARO) Sensor (F96).


VAG Error Code: 17912
EOBD II Error Code: P1504

Fault Location:
Intake System - Leak Detected

Possible Cause:
Malfunction Indicator Lamp (MIL)(K83) active.

Intake leak.
Exhaust Gas Recirculation (EGR) system.
Evaporative Emission (EVAP) System.
Hose connection(s).
Throttle control unit.




That implies either an EGR issue or you have a vacuum leak.

Same issue here. http://www.volkswagenforum.co.uk/showthread.php?t=11474

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Re: Replacement engine

Post by alexperkins » Tue Jan 09, 2018 1:31 pm


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Re: Replacement engine

Post by littlepolo » Tue Jan 09, 2018 2:11 pm

Thanks for the info.

Ran out of time today but unplugging the MAP sensor seemed to have no effect (engine hot) other than throwing a code whereas unplugging the EGR did (idle settled after a few throttle blips and a few minutes). I adapted the EGR and throttle again while the engine was at operating temp. No change.

Put the vacuum gauge back on. Steady 16 at a fast idle. It's a bit low but drops near zero and bounces back near 25 on throttle blip.

I'll try again tomorrow and run it from cold. Can I drive for a few km with the EGR unplugged once its warn to verify it is at fault?

If EGR is faulty what is the minimum quality I need to ensure no further problems (at least not this year)?

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Re: Replacement engine

Post by alexperkins » Tue Jan 09, 2018 2:14 pm

Vacuum sounds ok now

EGR wise. Bosch or OEM. I’ll dig out some links for you with part numbers

And yes, you can unplug the EGR. It might throw an error but should behave itself

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