compression test

Post by **T'Onion** » 01 Feb 2007, 11:04

Ok i've finished re-building the 2.1 and was thinking about doing a compression test on it , just to check things out
Do i do a wet or dry one ? does it matter ?

Post by **Simon Baxter** » 01 Feb 2007, 11:54

I would run it first Mark.
If you compression test an engine that has just been built it will only concern you as the readings you get are likely to be quite low.

The new rings won't have bedded into the new/honed barrels so compreesion will be quite low until it sorts itself out.

The idea of a dry test is to check the compression as the engine runs, if you do a wet test the idea is that the oil fills in the gaps and seals the piston rings for you to diagnose if the engine is low on compression because of worn piston rings.

I would say run it for 1000 to 1500 miles before you will get any readings that you would want to see!

Post by **T'Onion** » 01 Feb 2007, 12:02

Thanks for that Simon ,
will get around to fitting it
Just did a test and like you say it was low , only 5 to 6 bar

Post by **Mocki** » 01 Feb 2007, 12:03

shout if tha needs a hand fatboy!

Post by **T'Onion** » 01 Feb 2007, 12:06

Mocki wrote:shout if tha needs a hand fatboy!

will do Steve , just need to sort a pipe out , the steel one that has the gromet at the end that fits into the water pump (early water system)

I'm planning a week off next month/early march so i may think about fitting it then

Post by **Mocki** » 01 Feb 2007, 12:13

Andy had one at the hideout of doom, belongs to me, but wether its still there i dont know...... give him a bell......

Post by **T'Onion** » 01 Feb 2007, 12:17

Mocki wrote:Andy had one at the hideout of doom, belongs to me, but wether its still there i dont know...... give him a bell......

he'll not answer

Post by **Mocki** » 01 Feb 2007, 12:25

your prob right....... but its worth a try.....