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Engine Specific Info and Questions => IDI Engine => Topic started by: hodgy_7 on January 15, 2010, 11:20:23 am

Title: AAZ pump problem
Post by: hodgy_7 on January 15, 2010, 11:20:23 am
Hi I have a 1993 1.9 td vento 
a while ago the alt belt snapped and i was nerely home so just kept going.
I got home the car seemed to be running fine but the temp went quite high about 120 °c.
I replaced the belt started the car and it was realy rough and was like misfiring This is how the car will idle and will fill the place with smoke
if i pull the cold start out  the car seems to run alot beter  but still smokes abit.
so i am thinking it must be something to do with the pump as it will run 90%ok with the cold start on just idles high

some one i know had the same experiance with a vauxhall engine and he said the pump is cooled and if the belt snapes  the diesel pump overheats and brakes something
questions
Title: Re: AAZ pump problem
Post by: Vincent Waldon on January 15, 2010, 11:41:47 am
It sounds like on this particular engine by running without the alternator belt you also ran without the waterpump, which is why the engine temperatures climbed so high.  

So, the most likely scenario is that your engine has suffered damage from overheating: warped head, scored pistons, etc, something that has reduced your compression.  Poor compression = white smoke.  Or, the headgasket was damaged as the result of overheating and is now bleeding coolant into the engine.  Steam = white smoke.  

Advancing the timing (cold start handle) will improve combustion slightly even with reduced compression and therefore decrease the white smoke if it's due to compression issues.

The injection pump is self-cooled by the diesel fuel it pumps and would have not suffered any ill effects as the result of a missing alternator belt.  The good news is that you're not going to need a new injection pump.  ;)

Assuming my "alt belt = water pump on your version of the AAZ engine" theory is correct, best bet now is to do a compression test and assess the health of the engine.
Title: Re: AAZ pump problem
Post by: rabbitman on January 15, 2010, 12:45:53 pm
Quote from: Vincent Waldon on January 15, 2010, 11:41:47 am
It sounds like on this particular engine by running without the alternator belt you also ran without the waterpump, which is why the engine temperatures climbed so high. 

So, the most likely scenario is that your engine has suffered damage from overheating: warped head, scored pistons, etc, something that has reduced your compression.  Poor compression = white smoke.  Or, the headgasket was damaged as the result of overheating and is now bleeding coolant into the engine.  Steam = white smoke. 

Advancing the timing (cold start handle) will improve combustion slightly even with reduced compression and therefore decrease the white smoke if it's due to compression issues.

The injection pump is self-cooled by the diesel fuel it pumps and would have not suffered any ill effects as the result of a missing alternator belt.  The good news is that you're not going to need a new injection pump.  ;)

Assuming my "alt belt = water pump on your version of the AAZ engine" theory is correct, best bet now is to do a compression test and assess the health of the engine.

X2
Title: Re: AAZ pump problem
Post by: burn_your_money on January 15, 2010, 03:32:33 pm
Do you have AC?

I would check the cam/crank timing just to make sure that it isn't the crank gear starting to spin.
Title: Re: AAZ pump problem
Post by: vanbcguy on January 16, 2010, 02:56:06 pm
Quote from: burn_your_money on January 15, 2010, 03:32:33 pm
Do you have AC?

I would check the cam/crank timing just to make sure that it isn't the crank gear starting to spin.

Good call - if the crank pulley is starting to wobble that could easily cause it to toss the alt belt too...
Title: Re: AAZ pump problem
Post by: hodgy_7 on January 16, 2010, 03:25:15 pm
Thanks for the replys
yes the alt belt does spin the water pump on  my engine.it doesnt have A/C
I will try and get it inside next week some time and get a compression test done
i was driving it every day for about 2 weeks after this happend (had no choice only mode of transport to work) and it didnt loose any coolant or over heat once, power is down abit but it still kept up with my brothers 95 passat 19tdi

i hope i dont need a new injection pump because i think they are about as rare as rockyhorse sh1t at the minute.. i blame our govermnt and there stupid scrappage scheme  every one has scraped there old cars  and got £2000 off a new car with it
Now there arnt many old cars sitting around or geting broke for parts

once again thanks for  the help