proxlamus© Posted January 3, 2007 Share Posted January 3, 2007 hmm .. mine still ticks.. at idle after running after a bit.. this sucks.. I cleaned EVERYTHING.. maybe I over tightenend them.. dang.. back again Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted January 3, 2007 Author Share Posted January 3, 2007 I measured one of mine while i had them apart and got about 0.0005" diameter difference between the bore and the top piston. I can't tell you the accuracy of that measurment because technically it's outside the precision of the vernier that I used. I should have used a micrometer but didn't have one handy. You might want to check them with eachother to see if one is worn or damaged. Is the cold weathermaking it worse? Try thinner oil. Quote Link to comment Share on other sites More sharing options...
twoeightythreez Posted January 3, 2007 Share Posted January 3, 2007 If they pop up and are tight when you loosen them, they were overtight for sure....u probably did overtighten them, I did that to mine, too, initially. If you don't have a torque wrench, just barely "snug" them. It's not like they're going anywhere. (It's amazing how easily you can apply 30ft-lb when using a 1/2" ratchet, which is likely since the lifter is 24mm diameter!) (1/8 turn should be the MOST you turn them after they seat by hand) Quote Link to comment Share on other sites More sharing options...
proxlamus© Posted January 3, 2007 Share Posted January 3, 2007 could be! it is 10* F outside.. and have had 6 feet of snow in less than a month.. LoL but it only ticks after like a 5 mile drive.. and the engine warms up.. oil pressure is low at idle.. sitting at a stop light then tick tick tick tick Quote Link to comment Share on other sites More sharing options...
twoeightythreez Posted January 3, 2007 Share Posted January 3, 2007 I'm happy so far with mine...I just hope I didn't damage the engine yesterday...my el cheapo electric fan broke without me knowing, I was messing with the MS tuning and wasn't paying attention to temp, when all of a sudden I saw the engine was at 240 deg...I hope it's alright as it was at idle. (The lifters weren't even ticking at 240!) That gotta be good for the state of my lifters. Quote Link to comment Share on other sites More sharing options...
proxlamus© Posted February 19, 2007 Share Posted February 19, 2007 well.. today I torqued them to spec and noticed something interesting.. the holes in the lifters did NOT line up with the holes on the head... hmm.. i wonder if each lifter has its own "home"... since I converted over to solids then BACK to hydraulics.. they were in a box.. and were not placed exactly in the same spot. Is each lifter different?! like a different thread start, or different depth or something?! I used a sharpie to mark the lifter to see if it lined up.. hmm Quote Link to comment Share on other sites More sharing options...
GrayZee Posted February 19, 2007 Share Posted February 19, 2007 I noticed that about the oil hole alighnment too.. but no, I don't think it matters. It'll just fill the whole area with oil then the the pressure will rise inside. Quote Link to comment Share on other sites More sharing options...
proxlamus© Posted February 19, 2007 Share Posted February 19, 2007 cool. thanks man! Quote Link to comment Share on other sites More sharing options...
twoeightythreez Posted February 20, 2007 Share Posted February 20, 2007 the oil hole not lining up......is why you can't overtorque them. If you tighten the shisniegen out of them you're blocking the oil supply to the lifters! Notice how the oil hole in the lifter body seats on the machined flat surface of the head. I think at 30 ft/lb there is still enough clearance between the surfaces to get oil to the lifters. Any tighter and they work for 5 min but slowly bleed down and cause major headaches. (WHen mine were ticking I was able to move them easily up and down by hand, I loosened them and they popped RIGHT up...then I torqued them to about 30ft/lb and they've been fine ever since.) Quote Link to comment Share on other sites More sharing options...
Guest Hyksos Posted June 25, 2007 Share Posted June 25, 2007 I wanted to do the cleaning on my hydraulic lifter ... but oh horror ... I found mine was converted to solide lifter!! Or do I have a P90 solid head??? I have a 1983 turbo .... so only way I can have a solid head is if the owner before me changed the engine or head ... How can I know if I have a P90 or P90a head? Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted June 25, 2007 Administrators Share Posted June 25, 2007 Don't panic. The little casting numbers on the side of the head will either read P90 or P90A. Now keep in mind, not all P90A heads were hydraulic. Some were cast and manufactured with mechanical lifters. So in short, as long as there is a "P" a "9" and a "0" as the casting number, your good. The "A", well, it really means squat as the head coud be either hydraulic or mechanical, so just ignore it. Instead of horror, you should be kneeling before the gods of internal combustion, say a little gracious thank you prayer, then promptly get your .010" and .012" feeler gauges and adjust your valves, start your engine and dirive away a happy happy man. Quote Link to comment Share on other sites More sharing options...
NewZMan Posted September 28, 2007 Share Posted September 28, 2007 I want to thank everyone for this helpfull info. I had lifters on 5 and 6 ticking like crazy. I followed the instructions here and now it purrs like a kitten. NO TICKS. Thanks for savin a poor guy lots of money!!! Quote Link to comment Share on other sites More sharing options...
niner11 Posted September 28, 2007 Share Posted September 28, 2007 Cygnusx1, I never thought about it till I saw your pics but did you ever measure all of the lifter springs and see if there were differences between them. I bet McMaster-Car would have something to replace them. Chuck Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted September 28, 2007 Author Share Posted September 28, 2007 The springs are not really critical. The retention of oil inside the lifter body is critical. The oil trapped inside the lifter acts as a solid lifter. When the oil bleeds out, the lifter crunches. The spring is there just to keep them taught even with no oil pressure when the engine is off. Quote Link to comment Share on other sites More sharing options...
dano Posted June 6, 2010 Share Posted June 6, 2010 holy resurrected thread Batman! I'm going through the headache that is dirty hydro lifters and was hoping you folks could help me out with a few issues I'm having. First of all I'm doing this with the head still on the motor. Not sure if it matters or not but this is a freshly build motor (~35mi on it). I'm using the KD 3087 valve spring compressor to help with rocker arm removal and installation. The first few valves (specifically #11) went just fine. Then I got to #6 and #7 and am having issues. Basically when I compress the valve spring with the KD tool, the valve only opens a bit and seems to get stuck. I noticed it at first when the lash pad would not go down with the spring retainer ring. I've compressed the spring several times and the valve is still doing the same thing. I've checked to make sure the valve wasn't touching the piston. I'm really concerned that I'm going to drop a valve at this rate. Any advice or ideas? Thanks in advance! -Dan P.S. Thanks a TON to cygnusx1 for pointing me to the KD 3087. It's made all the difference. Quote Link to comment Share on other sites More sharing options...
paul vixie Posted July 13, 2010 Share Posted July 13, 2010 Resurrecting this thread again after six years. I followed these instructions, mostly, and got spectacular results. I'm starting to think that Nissan made a mistake in not including rebuild instructions on these lifters -- FSM says if they go bad you replace them, but after cleaning a whole set from a Pick&Pull P90A, I can't imagine how they'd wear out. This thread should not just be sticky, it should have been in the FSM all along. The use of a Sharpie is pure genius and works perfectly, I would never have thought of this. My read on this is, there are three failure modes for this lifter. Ball check valve stuck open or stuck closed, air bubble below the ball check valve, or scoring on the piston or cylinder. The first two are amenable to cleaning. The third one would have to be really bad before you'd throw a lifter away. They don't bleed down when the motor's off. The ball check valve says, once the oil's in, it's in. This is a terrible design, since with no bleed-down and no flow-by, the oil that's in there is from the factory or from the last time you cleaned the lifters. In my case it was old and carbonized and there were some stuck-open and jammed ball valves from the oil-carbon particulates. The guy who told me to try engine cleaner was nuts -- there's no way for it to get in there. I did not use a spring compressor since there was no way to get it in there with the head on the car. A screwdriver, using the cam for leverage, and careful not to go metal-on-metal on the shiny places, got the springs down far enough for me, all 24 times (12 out, 12 in.) I did not fully assemble them immersed in oil. I put the spring in after cleaning the barrel with Chem Dip and a round wire brush, and then immersed the barrel+spring in oil, got the bubbles out, and then put the smaller piston in after cleaning it also in Chem Dip and clearing the particulates out of the ball valve. The small piston stops when it reaches the oil supply hole in the barrel, since there's nowhere for the oil to go and it doesn't compress. So then i took it out of the oil bath, dripped and wiped off the excess oil, put it down on the bench, and put two small allen hex keys into it. One hex key was in the center, to release the ball check valve, and one was off to the side, so i could compress the bigger spring under the smaller piston. This was the only tricky part: letting the ball valve close before letting the piston off the spring. With that dance, the larger piston went in far enough that the hat clicked into place easily. I have a junk yard P90 head that I'll put in at some convenient time. Meanwhile I'm extremely grateful to all of you for this forum and this thread, I've now got low end torque again, I think I had an Inline 5 until this evening. THANKS, ALL. Quote Link to comment Share on other sites More sharing options...
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