nells vr6 0 Posted January 17, 2006 Report Share Posted January 17, 2006 when a compression test is done what kind of results am i lookin for to suggest the cylinder head gasket as gone or on its way out just so i can compare when mine gets tested thanks Link to post Share on other sites
andy 0 Posted January 17, 2006 Report Share Posted January 17, 2006 The pressures in each cylinder should all be similar, I think an overall spread of 10% either side of the middle values is ok. If you have a dodgy head gasket you may see low pressure on one cylinder or a if the gasket has gone between cylinders a pair of adjacent low readings. My last test showed between 170 and 190 on all 6 which seems fine to me, its done 110k miles without any engine work. Remember there are many things that can cause low readings, not just the headgasket. Link to post Share on other sites
nells vr6 0 Posted January 17, 2006 Author Report Share Posted January 17, 2006 i need to get it checked asap as my car seems to be boiling over and the aa said it may be the gasket and i think water is getting in to the oil somewhere small traces of the dreaded mayo unless its the oil cooler Link to post Share on other sites
andy 0 Posted January 17, 2006 Report Share Posted January 17, 2006 It may be the gasket, it could also be a jammed thermostat amongst other things, that can make them boil up pretty quick, or a leaking coolant hose. A compression test is a nice quick way of giving a rough indication of what's wrong. Keep us updated mate. Link to post Share on other sites
jayvwvr6 0 Posted January 17, 2006 Report Share Posted January 17, 2006 nells,were are you finding the traces of water mixing with the oil?mines been showing a bit of mayo under the oil cap,ive had test done and nothing showing up?but im not getting the overheating problem. Link to post Share on other sites
kilokilla 0 Posted January 17, 2006 Report Share Posted January 17, 2006 firstly thermostat wont cause oil and water mayo mix but oil cooler most defo will and if you get oil water mix it will cause to overheat thirdly easiest way to check for head gasket is a tester that just goes on water bottle and changes colour if gasket knackered.also jay if your breathers arent perfect or your little black valve isnt in good condition on rocker cover it can cause oil not to breathe properly which can cause condensation in oil causing bit of cream in oil cap i find this happens more if car used mainly for short journeys. Link to post Share on other sites
andy 0 Posted January 17, 2006 Report Share Posted January 17, 2006 A stuck thermostat is still possible, quite a few people notice slight mayo when they only use the car infrequently or as you say for short journeys. Link to post Share on other sites
matth76 1 Posted January 17, 2006 Report Share Posted January 17, 2006 How easy is it for this compression test to be done? Is it one or two hours work and what do these tests cost roughly? Link to post Share on other sites
Eat this 2 Posted January 17, 2006 Report Share Posted January 17, 2006 i think it plugs into where the sparkplugs go then remove all the leads and crank the engine Link to post Share on other sites
matth76 1 Posted January 17, 2006 Report Share Posted January 17, 2006 Thanks. Is specialised equipment needed then? I'm seeing The Phirm this saturday - is this something they can do? Link to post Share on other sites
kilokilla 0 Posted January 17, 2006 Report Share Posted January 17, 2006 sorry andy your quite right i was just pointing out that that it wouldnt cause the oil to mix with the water mate wasnt trying to contradict you i should have been a little more specific. Link to post Share on other sites
andy 0 Posted January 17, 2006 Report Share Posted January 17, 2006 No worries mate ;-) Link to post Share on other sites
andy 0 Posted January 17, 2006 Report Share Posted January 17, 2006 Thanks. Is specialised equipment needed then? I'm seeing The Phirm this saturday - is this something they can do?Nothing particularly specialised, its just a pressure guage that screws into the plug holes. You can buy them for £10 or £15 or so. I've got one and its the best diagnostic tool I've ever owned! Takes me less than an hour to check a 6 pot. Some garages may have more elaborate equipment than that though, that can tell you more about where you are losing pressure, so it may take them longer. Link to post Share on other sites
petervr6 0 Posted January 17, 2006 Report Share Posted January 17, 2006 were are the oil coolers on the vr then how can you tell if it had it. i had my headgasget done bout 2000 miles ago along with my water pump thermostat and expan tank cap my water hose are not rock hard you can just sqezze them together but im getting a dribble of coolant from the hole in the side of the expansion tank think its the bottom 1 out of the 2 as there are 2 small hole there any ideas kilokilla asked you bout this the other week. jus checked my hoses after a drive. Link to post Share on other sites
petervr6 0 Posted January 20, 2006 Report Share Posted January 20, 2006 anybody have any ideas? Link to post Share on other sites
jayvwvr6 0 Posted January 20, 2006 Report Share Posted January 20, 2006 my hoses are soft untill the car been running for a bit and the pressure has built up then you cant sqeeze them together,i get a bit ot coolant come out of expansion bottle but only if its over filled it then finds its level and doesnt leak.as for the oil cooler it sits at the front of the engine its a square alloy unit with 2 small collant hoses going to it,there prone to leaking oil the seals go and drip oil down the front of the block,as for when they fail i dont know on that one mate what to look for. Link to post Share on other sites
jayvwvr6 0 Posted January 20, 2006 Report Share Posted January 20, 2006 my hoses are soft untill the car been running for a bit and the pressure has built up then you cant sqeeze them together,i get a bit ot coolant come out of expansion bottle but only if its over filled it then finds its level and doesnt leak.as for the oil cooler it sits at the front of the engine its a square alloy unit with 2 small collant hoses going to it,there prone to leaking oil the seals go and drip oil down the front of the block,as for when they fail i dont know on that one mate what to look for. Link to post Share on other sites
petervr6 0 Posted January 21, 2006 Report Share Posted January 21, 2006 ye sorry you can sqezze them together but its vey hard an you can just about do it maybe the car wasnt that hot but hay must check that for oil leak as i do get a small bit of oil on me sump after a while thought it was my sump gasket but ill check that any ways any body else no why my water is doing the above thanks. Link to post Share on other sites
nells vr6 0 Posted January 23, 2006 Author Report Share Posted January 23, 2006 all my worries are sorted it was the thermostat that was causing the problem i have swapped it and all problems are sorted cheers or the help guys Link to post Share on other sites
andy 0 Posted January 23, 2006 Report Share Posted January 23, 2006 It may be the gasket' date=' it could also be a jammed thermostat amongst other things, that can make them boil up pretty quick, or a leaking coolant hose. A compression test is a nice quick way of giving a rough indication of what's wrong. Keep us updated mate.[/quote']Hehe, another one bites the dust! Getting good at this! Link to post Share on other sites
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