rusty bolts 0 Posted February 16, 2009 hi guys just a quick question, valves guides? how hard are they to be replaced do they really need to be pressed out then the new ones frozen and put in and for them to be machined to fit perfectly? iv sent my head off to be checked and for a skim but the guy is telling me the exhaust valve guides are shot? i dont know weather to trust him! and he wants £20 per cylinder! cheers any input most welcome! Quote Share this post Link to post Share on other sites
mrengine 0 Posted February 16, 2009 dont worry i have come across worn guides more so the exhaust than inlet does it smoke when you first start the vehicle in the morning that is usaully a good sign of nackerd guides :( :( hi guys just a quick question, valves guides? how hard are they to be replaced do they really need to be pressed out then the new ones frozen and put in and for them to be machined to fit perfectly? iv sent my head off to be checked and for a skim but the guy is telling me the exhaust valve guides are shot? i dont know weather to trust him! and he wants £20 per cylinder! cheers any input most welcome! Quote Share this post Link to post Share on other sites
davidwort 0 Posted February 16, 2009 He should have checked to see if the movement of the valves was within tolerance, it's worth doing if you already have the head off, otherwise any new stem seals won't last five minutes and it'll use oil again, although it's usually inlet guides that let the oil in as the flow is into the comb chamber rather than out like the exhaust. When my head was flowed (at approx 100,000 miles) the exhaust guides were replaced, so I guess they may wear quicker? Quote Share this post Link to post Share on other sites
rusty bolts 0 Posted February 16, 2009 well on the "when it starts" question i dont know lol i haven started it! i bought it on the word that it runs well with no bad sounds! from looking at it, everything looks well and good! its good to hear that you had to have your valve guides replaced at 100k sounds like its kinda normal from what ive been reading il let you know how it goes! oh does it sound like a fair price £105 for skim and 8 vavle guides put in? cheers guys! Quote Share this post Link to post Share on other sites
davidwort 0 Posted February 16, 2009 sounds fair to me, it's not a 5 minute job. Quote Share this post Link to post Share on other sites
VEEDUBBED 0 Posted February 17, 2009 Or do it yourself like i did,no special tools exept a special valve seal remover i bought years ago at a tool fair.You'll have to make up a punch,i made one out of an old turbo wastegate actuator arm ground down so it fit inside the guide. 1 very important thing to remember is BEFORE removing any guides,measure the guide's height from inside the cyl. head first,use a Vernier caliper and see how much the guide's sholder potrudes,mine were 11mm. Once i didn't do this and then wondered why my newly re-built 16v head smoked worse than when i blew the turbo,the hyd. tappets hammerd the new stem seals to death because the guides were fitted too high in the head... I changed all 16 guides without heating anything,i didn't even bother to lubricate the guides with oil,i just sat the head on a flat block of wood and hammered the fookers untill they were spat out the combustion chamber side. No problems at all :D Quote Share this post Link to post Share on other sites
Roger Blassberg 0 Posted February 18, 2009 The only engine in which I ever changed valve guides was a BMC A series (Austin Cooper S). The valve seats needed re-cutting afterwards to centralise them with the guides. Is that necessary with this engine, in which case you will need some special cutters? Best wishes RB Quote Share this post Link to post Share on other sites
davidwort 0 Posted February 18, 2009 The only engine in which I ever changed valve guides was a BMC A series (Austin Cooper S). The valve seats needed re-cutting afterwards to centralise them with the guides. Is that necessary with this engine, in which case you will need some special cutters? Best wishes RB I'd say yes, can't see you should ever put new valves or guides in without lapping them in. Quote Share this post Link to post Share on other sites
