carbers205 1 Posted January 14, 2008 Hello people. Seems much like my XU10J2C bottom end has given way on me. Been having a few probs with the car recently not least some random temperature fluctuations and water disposal through the overflow pipe! Anyway, driving home on Sat I start to hear a strange knocking noise. As I pull up to some lights the oil pressure drops right away having previously been fine and all sense of acceleration then disappears. Doh. It seems to be a definite knocking rather than ticking....Ive had a shim displace itself before but this certainly sounds different. Did a quick comp test once I got home and found 155, 170, 145, 175 and this is on a newly rebuilt head. Just as a comparison the test before rebuild and before knocking came back as 155, 170, 170, 170. The head has been skimmed and crack tested and also double checked. The valves have been compression tested too as they were done to 3-angle when the head was last off. Soooo, does everyone concur with my diagnosis and if so where do I go next?! Having spent a few quid on getting the head flowing right and with the XU9 cam on Im reluctant to throw the whole engine. Is it wise move to get a new XU10 block and strap my existing head on it? I was really hoping for a reasonable increase in power for my work but things are just getting worse! Ultimately Id like to be able to build quite a high spec engine but Im not sure where this leaves me in my quest, especially as I have very little money left! All thoughts greatfully received! Andy Share this post Link to post Share on other sites
davemar 16 Posted January 14, 2008 I'm not how a compression test will reveal a bottom end problem apart from piston ring trouble; though your number to seem a point to a problem of some sort. If you want to check the bottom end a bit more you could drop the sump off (remove oil first unless you want to look like Peter Andre), and remove each of the big-end journals and have a look at and maybe measure the big-end bearings. You can spin out the top ones too easily enough. You can do all this without removing the crank, although it's a bit of a faff with all those sump bolts and crawling on your back. It's worth nailing the problem early with the bottom end, as you don't want to have it rapidly wearing out your crank which might end up ungrindable. Share this post Link to post Share on other sites
