 96mm Big Bore, Rings - Advice Needed |
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| 74914LE |
 Jul 26 2004, 08:56 AM
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#1
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Member  Group: Members Posts: 136 Joined: 6-April 04 From: Fort Worth, TX Member No.: 1,895  |
Advice Needed:
The engine that the 96mm Big Bore Kit (1.8ltr) is installed in is a 1.7ltr that has the heads fly cut to accept the larger size. (This is an NPR kit from about 12 years ago) Before the new set up had 25 miles on it, #3 exhaust valve came loose in the seat. Killed the motor before things got out of hand, and fixed this problem. From the looks of the tops of the pistons, the setup was running too rich. Now that I am ready to put things back together, I know that I should have the glaze taken off the cylinders, (The original honing is still visible on them) and clean the carbon off the pistons. My question is should I, or do I have to replace the rings? They look almost brand new, and there is nothing to clean from inside the grooves on the pistons. I picked up a set to install, but I do not want to waste perfectly good rings, if these will seal if given the opportunity. Your thoughts are appreciated. 74914LE |
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| akellym |
Jul 26 2004, 11:54 AM
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#2
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Eyes Of The Deep Battle Group: Members Posts: 597 Joined: 25-July 04 From: Annandale, MN Member No.: 2,395 Region Association: Northstar Region |
Why take the chance. I sure wouldn't want to take all a part again.
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| Jake Raby |
Jul 26 2004, 12:21 PM
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#3
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Engine Surgeon Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
Replace the rings if the end gap when installed in the cylinder half way down the bore (ensre it totally square in the bore using a piston as a guide) are worn to the point where a .023 feeler gauge can be slid through them...
I would replace them anyway if it were my engine.... ENSURE if you replace them that you DO NOT use Grant rings! |
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| Targa |
Jul 26 2004, 02:17 PM
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#4
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V Member Group: Members Posts: 180 Joined: 26-December 02 From: San Mateo, CA Member No.: 18 |
Jake,
What type of rings would you use instead of Grant? Deeves? Total Seals? |
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| Brett W |
Jul 26 2004, 02:43 PM
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#5
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Advanced Member Group: Members Posts: 2,856 Joined: 17-September 03 From: huntsville, al Member No.: 1,169 Region Association: None 
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Hastings are good rings, Total Seals are not worth the money. Been down that road. Deves are good although I hear they are a little hard. Grant's suck ass.
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| Jake Raby |
Jul 26 2004, 02:43 PM
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#6
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Engine Surgeon Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
Hastings are all we use.. Total seals and a TIV don't get along!
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| Targa |
Jul 26 2004, 04:53 PM
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#7
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V Member Group: Members Posts: 180 Joined: 26-December 02 From: San Mateo, CA Member No.: 18 |
What would your opinions be on using the hastings rings with a total seal 2nd ring only?
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| Brett W |
Jul 26 2004, 05:53 PM
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#8
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Advanced Member Group: Members Posts: 2,856 Joined: 17-September 03 From: huntsville, al Member No.: 1,169 Region Association: None
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No don't bother. Engines need some blowby to make the rinds work properly.
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| 74914LE |
Jul 26 2004, 06:07 PM
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#9
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Member Group: Members Posts: 136 Joined: 6-April 04 From: Fort Worth, TX Member No.: 1,895 |
As it turns out, they are Grant's. Looks like I will be
doing some guage work to verify if the set currently on the pistons will work. Thanks for the heads up on the Grant's. Next time I will be very specifc with what I ask for from the parts house. Thanks! |
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| Jake Raby |
Jul 26 2004, 06:17 PM
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#10
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Engine Surgeon Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
DO NOT USE TOTAL SEALS!!
trust me, I lost about 6,000 bucks figuring out that they don't work! |
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| Targa |
Jul 26 2004, 07:40 PM
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#11
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V Member Group: Members Posts: 180 Joined: 26-December 02 From: San Mateo, CA Member No.: 18 |
Thanks Jake and Brett for the advise and learning things the hard way for myself and everyone else too so we don't have to! (IMG:style_emoticons/default/beer.gif)
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| 74914LE |
Jul 26 2004, 08:03 PM
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#12
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Member Group: Members Posts: 136 Joined: 6-April 04 From: Fort Worth, TX Member No.: 1,895 |
Jake,
Any idea what the rings are that came stock with this NPR set up? It was purchased in 1992. The oil ring has a pull apart spring in the middle that sits behind the center part of the ring. These Grant's that I just purchased have a three piece oil ring arrangement. The center part looks corrogated. |
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| Jake Raby |
Jul 26 2004, 08:41 PM
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#13
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Engine Surgeon Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
NPR stands for "Nippon piston ring" and thats what the older NPR sets used for rings. They are good but they do have some blowby issues with higher cylinder pressures.
Hastings makes a replacement ring, we use them.. |
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