Converting a L98 tensioner to replace a 10067479 - ZR-1 Net Registry Forums

2poor4aZR1 · 04-11-2023

So I had a not so great idea of trying to convert a tensioner out of a L98 to fit my LT5. I had a free/bad tensioner from an L98, and figured why not try instead of waiting around for someone to post one. Working from pictures, I've been pretty successful with the modification, but still have more work to do. Also, I want to throw out there that this was my first time welding aluminum, and I ran a 75/25 mix when I really should have used 100% argon. While I'm not sure that any of this will be of use to most people, someone out there one day might find some use for the pictures. As mgbrv8 said 10 years ago, they are "rarer than a supermodel at a buffet" which with time will only get worse. This guide also might help with anyone needing to rebuild their old tensioner, since the process is the same for both the L98 and LT5 tensioner.

Disassembly:

I recommend spraying the inside of the tensioner and the center shaft with a liberal amount of PB Blaster the night before as the pressed on cap can be very seized up depending on where your ZR1 lives. To remove the cap, use two screw drivers or pry bars can be used on opposite sides of the cap to slowly work it off.

IMG_20230406_234740.jpg IMG_20230406_234918.jpg

Using a long bolt, nut, and washers , I capture the pivot arm and base to keep them from flying all over the place. Using two screw drivers or pry bars, separate the base from the pivot arm. Be careful and keep your fingers away from the tensioner, as the energy released can hurt you (ask me how I know).

IMG_20230410_223352.jpg

Now, if you are rebuilding your tensioner, at this point you'd take the coil spring(with the new nylon), cap spring (pt3), and plastic bearing (pt 9) from the Dayco 89298 to transplant into your 10067479 tensioner.

(Thank you mgbrv8 for this very helpful diangram)

The bearing with the cam (pt 7) is different from the one found in the Dayco 89298 (lt5 tensioner), and will need to be retained. mgbrv8 recommends removing the cam on the new one, however it does serve a purpose and shouldn't be swapped unless your original one is damaged. If it is damaged and you want to replace it, you can technically scavenge one from a Dayco 89219 (1998 Dodge Ram 3500 with 5.9 diesel). This is how I acquired mine and can confirm against the L98 tensioner that it is properly 180* out. The spring and the rest of the unit is basically scrap, so expect to spend $90 on the single part.

Modifying the L98 tensioner

Now, for the L98 tensioner, the first difference I tackled was the limit stops cast in to the pivot arm. The Dayco 89298 is clocked differently than the 89298, and will need to have the built up with weld. I used a spool gun to build up the areas, then used a file followed by a pneumatic sanding disk to clean it up.

IMG_20230407_152325.jpg

Grinder and paint makes me the welder I aint.

04-11-2023	#1
2poor4aZR1 Join Date: Mar 2023 Location: Texas Posts: 34	Converting a L98 tensioner to replace a 10067479 So I had a not so great idea of trying to convert a tensioner out of a L98 to fit my LT5. I had a free/bad tensioner from an L98, and figured why not try instead of waiting around for someone to post one. Working from pictures, I've been pretty successful with the modification, but still have more work to do. Also, I want to throw out there that this was my first time welding aluminum, and I ran a 75/25 mix when I really should have used 100% argon. While I'm not sure that any of this will be of use to most people, someone out there one day might find some use for the pictures. As mgbrv8 said 10 years ago, they are "rarer than a supermodel at a buffet" which with time will only get worse. This guide also might help with anyone needing to rebuild their old tensioner, since the process is the same for both the L98 and LT5 tensioner. Disassembly: I recommend spraying the inside of the tensioner and the center shaft with a liberal amount of PB Blaster the night before as the pressed on cap can be very seized up depending on where your ZR1 lives. To remove the cap, use two screw drivers or pry bars can be used on opposite sides of the cap to slowly work it off. IMG_20230406_234740.jpg IMG_20230406_234918.jpg Using a long bolt, nut, and washers , I capture the pivot arm and base to keep them from flying all over the place. Using two screw drivers or pry bars, separate the base from the pivot arm. Be careful and keep your fingers away from the tensioner, as the energy released can hurt you (ask me how I know). IMG_20230410_223352.jpg Now, if you are rebuilding your tensioner, at this point you'd take the coil spring(with the new nylon), cap spring (pt3), and plastic bearing (pt 9) from the Dayco 89298 to transplant into your 10067479 tensioner. (Thank you mgbrv8 for this very helpful diangram) The bearing with the cam (pt 7) is different from the one found in the Dayco 89298 (lt5 tensioner), and will need to be retained. mgbrv8 recommends removing the cam on the new one, however it does serve a purpose and shouldn't be swapped unless your original one is damaged. If it is damaged and you want to replace it, you can technically scavenge one from a Dayco 89219 (1998 Dodge Ram 3500 with 5.9 diesel). This is how I acquired mine and can confirm against the L98 tensioner that it is properly 180* out. The spring and the rest of the unit is basically scrap, so expect to spend $90 on the single part. Modifying the L98 tensioner Now, for the L98 tensioner, the first difference I tackled was the limit stops cast in to the pivot arm. The Dayco 89298 is clocked differently than the 89298, and will need to have the built up with weld. I used a spool gun to build up the areas, then used a file followed by a pneumatic sanding disk to clean it up. IMG_20230407_152325.jpg Grinder and paint makes me the welder I aint. Last edited by 2poor4aZR1; 04-11-2023 at 01:57 AM.