compression figures petrol

[jaylo264]

Can anyone tell me whether 7-8 bar , i.e. 100-120 lbf/in2 , on all cylinders of a DG 1.9 , done 135k , is reasonable ? ; improves to c . 150 when oil squirted in pots ; engine runs ok , oil consumption good , no water useage ; it's just feelin` tired now and giving me worries about drive to barca in july.
? Jaylo

[KarlT]

I think that's pretty bloody good.

[T'Onion]

it is a little low

according to the bentley

nominal 10-13 bar (145-189 psi)
minimum 8 bar (116 psi)
max. diff between cylinders 3.0 bar (44 psi)


lets see if laurie can offer some advice

[toomanytoys]

You could adjust the tappets on the lifters.. set them at 1/4 to 1/2 turn from just touching (Hydraulic tappets only!!) this may improve the results a little too.. (NOT the 2 turns Haynes spec)
is it smoking much?

The carb would benefit from a full rebuild, kits are cheap and available from GSF and VW...
cap rotor and leads in good nick? quality plugs? and a clean air filter...
Good quality 15w40 or (during the summer and a long trip like that) a 15w50 or 20w50...

Things like tyre pressures make a big difference too.. and even cheapo tyres..

[jaylo264]

thanks , toomanytoys , and others , do you therefore mean that i should ignore the compression test , like , and follow your good advice about tuning ,carb, etc ( tho most things are actually pretty ticketyboo -- but have never touched carb , being much too scared for our many years together by the yellow sign on top of the carb which says something like DANGER 10000000 volts KEEP OFF ! ).
Tyres are good , not a smoker really , but front disc squeeal ( now i remember !) makes me think there may be a little binding going on.
The thing is , i can certainly sort all these things , and will , BUT -- is it more likely to seize up or something on a trip , due to a cause connected with the low compression readings ?? In the absence of a crystal ball !
Grateful for all your input , and you may be saving me well over a grand , which will not be forgotten..........
Jaylo

[Fox McIntyre]

but have never touched carb , being much too scared for our many years together by the yellow sign on top of the carb which says something like DANGER 10000000 volts KEEP OFF !

Lawls. That waning is for the ignition system, not the carb. carb is 12v

[T'Onion]

are you anywhere near Mcgill , it would be worth popping along and letting them have a look / service it for you ..

http://www.syncro-nutz.com/index.html

[KarlT]

I think that's pretty bloody good.

I mean thats pretty good for 135,000 miles. Does it use oil?

[maxstu]

Toomanytoys,
is that...

Good quality 15w40 or (during the summer and a long trip like that) a 15w50 or 20w50...


15w40 normally and 15w50 or 20w50 during the summer and a long trip.
We're of to Spain in April. should I change to 20w50?
Regards
maxstu