B16C6 ring gap issues
#1
B16C6 ring gap issues
Hi, im rebuilding a B18C6 (EDM type-r) because of burning oil and low compression. Stock rebuild not all motor, boost...
-Cylinders look really nice when disassembled, it was cylinders honed and resurfaced in a Honda specialist in my country.
-Oem 81mm pistons de-carbonized
-Npr piston rings 81mm std.
I checked gap with new npr and old oem rings.
1st npr ring is 0.5 mm ring gap, oem is 0.4mm; service manual say it will be (0.2/0.35 new ring and 0.6 service limit)
2nd npr ring is 1.04 mm ring gap, oem is 0.65mm; service manual say it will be (0.4/0.55 new ring and 0.7 service limit)
3rd npr ring is 0.45 mm ring gap, oem is 0.4 mm service manual say it will be (0.2/0.5 new ring and 0.7 service limit)
Are normal this widths with npr rings? I sent a message to my dealer, because of this, 2nd ring is completly out of specs.
Many thanks.
-Cylinders look really nice when disassembled, it was cylinders honed and resurfaced in a Honda specialist in my country.
-Oem 81mm pistons de-carbonized
-Npr piston rings 81mm std.
I checked gap with new npr and old oem rings.
1st npr ring is 0.5 mm ring gap, oem is 0.4mm; service manual say it will be (0.2/0.35 new ring and 0.6 service limit)
2nd npr ring is 1.04 mm ring gap, oem is 0.65mm; service manual say it will be (0.4/0.55 new ring and 0.7 service limit)
3rd npr ring is 0.45 mm ring gap, oem is 0.4 mm service manual say it will be (0.2/0.5 new ring and 0.7 service limit)
Are normal this widths with npr rings? I sent a message to my dealer, because of this, 2nd ring is completly out of specs.
Many thanks.
#3
Re: B16C6 ring gap issues
Cylinder bores are:
1-81,04mm
2-81,04mm
3-81,05mm
4-81,04mm
Service manual std new is 81,00-81,02. Service limit 81,07.
I checked ring gap in different depths with same numbers in all cylinders.
1-81,04mm
2-81,04mm
3-81,05mm
4-81,04mm
Service manual std new is 81,00-81,02. Service limit 81,07.
I checked ring gap in different depths with same numbers in all cylinders.
#5
Honda-Tech Member
Re: B16C6 ring gap issues
Hi, im rebuilding a B18C6 (EDM type-r) because of burning oil and low compression. Stock rebuild not all motor, boost...
-Cylinders look really nice when disassembled, it was cylinders honed and resurfaced in a Honda specialist in my country.
-Oem 81mm pistons de-carbonized
-Npr piston rings 81mm std.
I checked gap with new npr and old oem rings.
1st npr ring is 0.5 mm ring gap, oem is 0.4mm; service manual say it will be (0.2/0.35 new ring and 0.6 service limit)
2nd npr ring is 1.04 mm ring gap, oem is 0.65mm; service manual say it will be (0.4/0.55 new ring and 0.7 service limit)
3rd npr ring is 0.45 mm ring gap, oem is 0.4 mm service manual say it will be (0.2/0.5 new ring and 0.7 service limit)
Are normal this widths with npr rings? I sent a message to my dealer, because of this, 2nd ring is completly out of specs.
Many thanks.
-Cylinders look really nice when disassembled, it was cylinders honed and resurfaced in a Honda specialist in my country.
-Oem 81mm pistons de-carbonized
-Npr piston rings 81mm std.
I checked gap with new npr and old oem rings.
1st npr ring is 0.5 mm ring gap, oem is 0.4mm; service manual say it will be (0.2/0.35 new ring and 0.6 service limit)
2nd npr ring is 1.04 mm ring gap, oem is 0.65mm; service manual say it will be (0.4/0.55 new ring and 0.7 service limit)
3rd npr ring is 0.45 mm ring gap, oem is 0.4 mm service manual say it will be (0.2/0.5 new ring and 0.7 service limit)
Are normal this widths with npr rings? I sent a message to my dealer, because of this, 2nd ring is completly out of specs.
Many thanks.
#6
Re: B16C6 ring gap issues
It sounds to me like the motor is not together and this is actual measurements while building. I'm not sure how your post about a running motor symptoms applies to a motor in the process of being assembled.
#7
Re: B16C6 ring gap issues
I send some e-mails to my dealer here in europe and to npr-japan:
My dealer:
Hi, in our opinion, NPR rings seem to be designed for “fit and forget” rather than “file and fit”. If you wish, we can also contact NPR’s support team but I will warn you not to expect a fast reply. Alternatively, you can send them back for a refund as they do not meet your requirements (we cannot do much about NPR’s tolerances, we are a reseller not the manufacturer in this case), thanks.
NPR-Japan:
Thank you very much for your e-mail.
We would like to investigate this NPR piston ring Part No. SWH30373ZZ that you
bought.
Could you courier us this ring with packages (box and label), please?
We are willing to cover the shipping charge.
We look forward to hearing from you.
Im going to buy OEM Honda and send back to my dealer, anyway i send meassurements to NPR-Japan.
My dealer:
Hi, in our opinion, NPR rings seem to be designed for “fit and forget” rather than “file and fit”. If you wish, we can also contact NPR’s support team but I will warn you not to expect a fast reply. Alternatively, you can send them back for a refund as they do not meet your requirements (we cannot do much about NPR’s tolerances, we are a reseller not the manufacturer in this case), thanks.
NPR-Japan:
Thank you very much for your e-mail.
We would like to investigate this NPR piston ring Part No. SWH30373ZZ that you
bought.
Could you courier us this ring with packages (box and label), please?
We are willing to cover the shipping charge.
We look forward to hearing from you.
Im going to buy OEM Honda and send back to my dealer, anyway i send meassurements to NPR-Japan.
Trending Topics
#8
Re: B16C6 ring gap issues
I send some e-mails to my dealer here in europe and to npr-japan:
My dealer:
Hi, in our opinion, NPR rings seem to be designed for “fit and forget” rather than “file and fit”. If you wish, we can also contact NPR’s support team but I will warn you not to expect a fast reply. Alternatively, you can send them back for a refund as they do not meet your requirements (we cannot do much about NPR’s tolerances, we are a reseller not the manufacturer in this case), thanks.
NPR-Japan:
Thank you very much for your e-mail.
We would like to investigate this NPR piston ring Part No. SWH30373ZZ that you
bought.
Could you courier us this ring with packages (box and label), please?
We are willing to cover the shipping charge.
We look forward to hearing from you.
Im going to buy OEM Honda and send back to my dealer, anyway i send meassurements to NPR-Japan.
My dealer:
Hi, in our opinion, NPR rings seem to be designed for “fit and forget” rather than “file and fit”. If you wish, we can also contact NPR’s support team but I will warn you not to expect a fast reply. Alternatively, you can send them back for a refund as they do not meet your requirements (we cannot do much about NPR’s tolerances, we are a reseller not the manufacturer in this case), thanks.
NPR-Japan:
Thank you very much for your e-mail.
We would like to investigate this NPR piston ring Part No. SWH30373ZZ that you
bought.
Could you courier us this ring with packages (box and label), please?
We are willing to cover the shipping charge.
We look forward to hearing from you.
Im going to buy OEM Honda and send back to my dealer, anyway i send meassurements to NPR-Japan.
#10
Honda-Tech Member
Re: B16C6 ring gap issues
send them back and get a new set, simple or take a chance and run these, since the gap is much wider expect more oil burning and white smoke at least from that cylinder.
#11
Re: B16C6 ring gap issues
I had ordered hastings/manning rings, these were way out of spec for 81mm - too loose. Mannings rings folks said that is how they are meant to be - ordered npr they were perfect. I think you got a bad batch.
Thread
Thread Starter
Forum
Replies
Last Post
sander
All Motor / Naturally Aspirated
3
03-29-2004 09:45 AM