Black deposits on pistons
- SWest
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Re: Re:Black deposits on pistons
03 Jan 2015 19:09
No you lap them in using lapping compound. Two stages, first the coarse grind, then the fine. What you are looking for is a pencil thin line around the vale and seat. There should be no dark spots anywhere they meet in the line. I do one at a time and put them back in chamber by chamber. Don't get sloppy with this stuff, it will grind everything if left in. Use valve stem grease listed in your manual. Don't get it the guides. Wash everything in solvent then soap and waster. Blow out all journals and make sure they're clean. I use my screw gun to lap the valves. A little forward, then back, check and do it again till it looks right. They sell lap cups but they're a pain the ass to use.
If a couple tries don't get a clean line, the valve is bent, don't try to use it. If you sand the gasket faces, do so in a circular motion especially around the oil passages. Go in a circle around them. It's harder for oil to seep past lines like that.
Put up pics of your progress and like always ask questions. There are plenty of people here to help.
Steve
If a couple tries don't get a clean line, the valve is bent, don't try to use it. If you sand the gasket faces, do so in a circular motion especially around the oil passages. Go in a circle around them. It's harder for oil to seep past lines like that.
Put up pics of your progress and like always ask questions. There are plenty of people here to help.
Steve
Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229
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- SWest
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Re: Re:Black deposits on pistons
04 Jan 2015 06:32 - 04 Jan 2015 06:36
I was re reading your question. The brass things you were asking about are the guides. You have to heat the head to remove them. If done wrong you can pull out metal with them, then you are in trouble. If the valve stems are
worn, you'll notice it, put them in the guide and rock it back and forth. If it does a lot, change the guides. If unsure how to do this, have it done. Sometimes metal will come out anyway. If that happens, oversize guide is called for. If unavailable, a new one can be put in a lathe and knurled. That creates a raised cross pattern that will fit in snugly.
Been there too. Hope you don't have to go there but I thought I should tell you before you do.
Steve
worn, you'll notice it, put them in the guide and rock it back and forth. If it does a lot, change the guides. If unsure how to do this, have it done. Sometimes metal will come out anyway. If that happens, oversize guide is called for. If unavailable, a new one can be put in a lathe and knurled. That creates a raised cross pattern that will fit in snugly.
Been there too. Hope you don't have to go there but I thought I should tell you before you do.
Steve
Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229
Last edit: 04 Jan 2015 06:36 by SWest. Reason: remove pic
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- Old Man Rock
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Re: Black deposits on pistons
04 Jan 2015 07:25
Piston domes... Simple Green is magic I see....
1976 KZ900-A4
MTC 1075cc.
Camshafts: Kawi GPZ-1100 .375 lift
Head: P&P via Larry Cavanaugh
ZX636 suspension
MIKUNI, RS-34'S...
Kerker 4-1, 1.5" comp baffle.
Dyna-S E.I.
Earls 10 row Oil Cooler
Acewell 2802 Series Speedo/Tach
Innovate LC1 Wideband 02 AFR meter
Phoenix, Az
MTC 1075cc.
Camshafts: Kawi GPZ-1100 .375 lift
Head: P&P via Larry Cavanaugh
ZX636 suspension
MIKUNI, RS-34'S...
Kerker 4-1, 1.5" comp baffle.
Dyna-S E.I.
Earls 10 row Oil Cooler
Acewell 2802 Series Speedo/Tach
Innovate LC1 Wideband 02 AFR meter
Phoenix, Az
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- Tyrell Corp
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Re: Re:Black deposits on pistons
04 Jan 2015 10:16KzChop82 wrote: As for, "head skim", to be honest I'm not really sure what that is...
But upon pulling the top end apart there was zero rust present on any of the components.
Not sure if that answers your question.
Look at the two 20mm squares on the top fin casting, under the exhaust valves on 1 and 4 ...if you put a straight edge on the head gasket face and a feeler guage there should be ? mm, when the head has been milled (skimmed) this measurement decreases. If you have 5 mins spare it would be really interesting.
(Sorry to cross post, just in your pics I can see the skim makers).
On the new rings, well worth doing. Is the consensus here that even if the installed ring end gaps were comfortably within service limit they should be changed anyway?
1980 Gpz550 D1, 1981 GPz550 D1. 1982 GPz750R1. 1983 z1000R R2. all four aces
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- SWest
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Re: Re:Black deposits on pistons
04 Jan 2015 12:30
The head has never been milled. If were to be milled the markers would be done as well. The rings should always be changed if possible, I've reused rings but there has be some leakage as a result. It will run but for $50 why take a chance? Just a drop in the bucket in the grad scheme of things.
Steve
Steve
Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229
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- KzChop82
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Re: Re:Black deposits on pistons
04 Jan 2015 13:15
I'm almost positive that even the valve cover had never been removed when I purchased the engine- let alone having mill work done...
Clinton, NJ
Custom chopper, 1982 KZ 1000 M2 CSR engine, K&N Pod Filters
PICTURES AND GOPRO VIDEOS!! :
www.dropbox.com/sh/jipz3l8nhzr4jge/AABbm...OC3sqlhCSLxH5Fa?dl=0
Custom chopper, 1982 KZ 1000 M2 CSR engine, K&N Pod Filters
PICTURES AND GOPRO VIDEOS!! :
www.dropbox.com/sh/jipz3l8nhzr4jge/AABbm...OC3sqlhCSLxH5Fa?dl=0
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- KzChop82
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Re: Re:Black deposits on pistons
04 Jan 2015 17:18
Did a profile update with some pictures and a go pro video.
www.dropbox.com/sh/jipz3l8nhzr4jge/AABbm...OC3sqlhCSLxH5Fa?dl=0
Took part all of the valves today and pulled the seals. I will post pictures tomorrow morning (at work
www.dropbox.com/sh/jipz3l8nhzr4jge/AABbm...OC3sqlhCSLxH5Fa?dl=0
Took part all of the valves today and pulled the seals. I will post pictures tomorrow morning (at work
Clinton, NJ
Custom chopper, 1982 KZ 1000 M2 CSR engine, K&N Pod Filters
PICTURES AND GOPRO VIDEOS!! :
www.dropbox.com/sh/jipz3l8nhzr4jge/AABbm...OC3sqlhCSLxH5Fa?dl=0
Custom chopper, 1982 KZ 1000 M2 CSR engine, K&N Pod Filters
PICTURES AND GOPRO VIDEOS!! :
www.dropbox.com/sh/jipz3l8nhzr4jge/AABbm...OC3sqlhCSLxH5Fa?dl=0
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- KzChop82
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Re: Re:Black deposits on pistons
04 Jan 2015 18:26
Pictures of the valves out:
Here are all four head valve areas:
But, one question- all of the interior studs (not the 4 exterior corners) have this debris by the foot of the post, where the stud meets the casing.
Are there supposed to be o rings here? Or is it just the degraded gasket over 30 years?
Thoughts?
Attachment ImageUploadedByTapatalk1420424230.713768.jpg not found
Attachment ImageUploadedByTapatalk1420424256.381655.jpg not found
Attachment ImageUploadedByTapatalk1420424277.950226.jpg not found
Here are all four head valve areas:
Attachment ImageUploadedByTapatalk1420424330.971282.jpg not found
Attachment ImageUploadedByTapatalk1420424344.122656.jpg not found
Attachment ImageUploadedByTapatalk1420424358.440239.jpg not found
Attachment ImageUploadedByTapatalk1420424371.924834.jpg not found
But, one question- all of the interior studs (not the 4 exterior corners) have this debris by the foot of the post, where the stud meets the casing.
Are there supposed to be o rings here? Or is it just the degraded gasket over 30 years?
Attachment ImageUploadedByTapatalk1420424540.339061.jpg not found
Attachment ImageUploadedByTapatalk1420424560.690620.jpg not found
Thoughts?
Clinton, NJ
Custom chopper, 1982 KZ 1000 M2 CSR engine, K&N Pod Filters
PICTURES AND GOPRO VIDEOS!! :
www.dropbox.com/sh/jipz3l8nhzr4jge/AABbm...OC3sqlhCSLxH5Fa?dl=0
Custom chopper, 1982 KZ 1000 M2 CSR engine, K&N Pod Filters
PICTURES AND GOPRO VIDEOS!! :
www.dropbox.com/sh/jipz3l8nhzr4jge/AABbm...OC3sqlhCSLxH5Fa?dl=0
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- SWest
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Re: Re:Black deposits on pistons
04 Jan 2015 19:35
Yup. I was right. Those valves look worse than mine did. That's a hard tail. Miller had a girder front end on his Hondadavidson. Inverted shock in place of the springs.
You might want to take a softer wire brush to the domes when you get it back together to smooth out ther scratches. Valve seats look normal for burning oil. May have preserved them. The exhaust valve was seating on the carbon like mine. Valve stem don't seem to have any wear marks? If not, you can clean the up and reuse them. The valve guides still look round. Are the exhaust steel or brass? The early KZ 1000's had steel and were known for fouling plugs. You might use some #600 paper to smooth the deck too. I take that back. My exhaust valves looked like yours, the intakes were still seating.
I bought some Kibblewhite valve springs on eBay for $68, I suggest you do the same. If they're weak, the valves won't seat or flutter on high rev. Z! has them too.
The valves should go in the same place they came from.
Steve
You might want to take a softer wire brush to the domes when you get it back together to smooth out ther scratches. Valve seats look normal for burning oil. May have preserved them. The exhaust valve was seating on the carbon like mine. Valve stem don't seem to have any wear marks? If not, you can clean the up and reuse them. The valve guides still look round. Are the exhaust steel or brass? The early KZ 1000's had steel and were known for fouling plugs. You might use some #600 paper to smooth the deck too. I take that back. My exhaust valves looked like yours, the intakes were still seating.
I bought some Kibblewhite valve springs on eBay for $68, I suggest you do the same. If they're weak, the valves won't seat or flutter on high rev. Z! has them too.
The valves should go in the same place they came from.
Steve
Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229
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- cpmaynard1980
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Re: Black deposits on pistons
04 Jan 2015 20:01
Reading over this makes me want to get back to work on my 77 kz1000. So much guidance. Ill be posting my own topic soon.
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- SWest
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Re: Black deposits on pistons
04 Jan 2015 21:14
Glad to be of some help.
Steve
Steve
Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229
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Re: Re:Black deposits on pistons
04 Jan 2015 21:18KzChop82 wrote: Pictures of the valves out:
Attachment ImageUploadedByTapatalk1420424230.713768.jpg not found
Attachment ImageUploadedByTapatalk1420424256.381655.jpg not found
Attachment ImageUploadedByTapatalk1420424277.950226.jpg not found
Here are all four head valve areas:
Attachment ImageUploadedByTapatalk1420424330.971282.jpg not found
Attachment ImageUploadedByTapatalk1420424344.122656.jpg not found
Attachment ImageUploadedByTapatalk1420424358.440239.jpg not found
Attachment ImageUploadedByTapatalk1420424371.924834.jpg not found
But, one question- all of the interior studs (not the 4 exterior corners) have this debris by the foot of the post, where the stud meets the casing.
Are there supposed to be o rings here? Or is it just the degraded gasket over 30 years?
Attachment ImageUploadedByTapatalk1420424540.339061.jpg not found
Attachment ImageUploadedByTapatalk1420424560.690620.jpg not found
Thoughts?
If you look closely you'll see some studs are open to the air.
Dirt can get in there..
Steve
Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229
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