Shortbusdriver Posted March 4, 2019 Share Posted March 4, 2019 Hi folks! New to the forum and hope to find answers to an issue I can't seem to figure out myself. My friend of 25 years has an 86 comanche that he loves and intends to keep for the rest of his life ( which may not be to long due to cancer returning). The issue is finding a new double v belt harmonic balancer for his 86 2.5 mj. All I can locate are the serpentine style that obviously won't work. I am hoping that someone here has the answer to this problem, I've seen reference to the 4.2 crank pully being the same as the 2.5 with the serpentine belt but have only seen the single v belt type online for the 4.2. I also ran across a dorman part that says it will fit the 2.5 (according to seller) but it is listed for chevy motors only elsewhere! ANY HELP would be appreciated! Link to comment Share on other sites More sharing options...
Pete M Posted March 4, 2019 Share Posted March 4, 2019 I can't say for sure, but the chevy idea definitely has merit. for better or for worse AMC used a ton of parts from other manufacturers. Link to comment Share on other sites More sharing options...
Shortbusdriver Posted March 4, 2019 Author Share Posted March 4, 2019 Thanks pete! According to my research so far AMC did use the GM (PONTIAC) 2.5 motor for a few years (early 80's)before creating there own 2.5 motor for the 1984/85 models. The amc motor is an I 6 minus 2 cylinders so the 4.2 balancer may fit the 2.5 , but I don't know for certain, and don't want to get any parts without knowing for sure! Link to comment Share on other sites More sharing options...
yxmj Posted March 4, 2019 Share Posted March 4, 2019 If it helps......non ac YJ'S used the double v-belt......with the 2.5 I am no expert but even though the front of the 2.5 and 4.0 are somewhat interchangeable (same water pump.....same t-stat housing ect) The balancer would be (IMHO) different... as it would obviously need to be balanced for cylinders 5&6? Link to comment Share on other sites More sharing options...
Jeep Driver Posted March 5, 2019 Share Posted March 5, 2019 6 minutes ago, yxmj said: If it helps......non ac YJ'S used the double v-belt......with the 2.5 I am no expert but even though the front of the 2.5 and 4.0 are somewhat interchangeable (same water pump.....same t-stat housing ect) The balancer would be (IMHO) different... as it would obviously need to be balanced for cylinders 5&6? Internally balanced and harmonics should be the same. Link to comment Share on other sites More sharing options...
Jeep Driver Posted March 5, 2019 Share Posted March 5, 2019 OP, go here, contact Submariner. He has your pulley. Link to comment Share on other sites More sharing options...
Shortbusdriver Posted March 5, 2019 Author Share Posted March 5, 2019 Thanks to all who have responded so quickly, I have used jeep drivers recommendation and will see if that pans out. In my search I contacted quadratek and was told that the serpentine belt style are the same part number for the 4 and 6 cylinder motors, but no double v style are listed. I did find a place in California that will rebuild the balancer but can't have the mj out of service more than a day, it's his only transportation . Link to comment Share on other sites More sharing options...
saveevryjp1998 Posted March 5, 2019 Share Posted March 5, 2019 I have what you need too I believe it doesn't pan out. I can get more as well. Link to comment Share on other sites More sharing options...
saveevryjp1998 Posted March 8, 2019 Share Posted March 8, 2019 This is what I have. It's a single serpentine setup. I have no clue if it's the same part # of the 4.0. I never thought about it until seeing your post. It took me almost a year to find a spare power steering pulley though. I come across v belt setups most of the time. Serpentine are much harder for me to find. 86s are tough to find period and there is many different belt configurations with different accessories making it worse with little info. Now I believe this is your setup. Everything in this pic accessory wise is up for grabs. The balancer is yours for cost of shipping like I said before. If you want more, same deal, but it would be cool if you would donate to Pete here at the club. I'm keeping the block, everything was running great so it's back up and it only has like around 100,000 I think on it. I'm using the auto trans and 207 to convert my 2wd mj with a bad clutch over solving 2 problems. I have a couple of spare aluminium 2.5 valve covers to sell too if your going that route. Link to comment Share on other sites More sharing options...
Shortbusdriver Posted March 8, 2019 Author Share Posted March 8, 2019 That looks right, I'll take it! I will revisit my searches again for more info on your serpentine set up but qtek said 4.0 and 2.5 are the same balancer. I did find crown # 3242886 is listed for both 2.5 and 4.2 motors 1981 to 1993, it has the shoulder on the back like yours appears to in the photos. I did run across mention that the alignment is off by 3/8 inch when using 4.0 pulleys , it could have to do with the shoulder being on the front or back of the pulley. How confusing it all is! Perhaps this info will be of use to others when all is said and done. I also found a dorman part (double v) that looks correct but it's listed for chevy , guess it will take finding all of the measurements ( id, od, offset, etc) to see if it will work on the 2.5 jeep motor. Link to comment Share on other sites More sharing options...
saveevryjp1998 Posted March 8, 2019 Share Posted March 8, 2019 59 minutes ago, Shortbusdriver said: That looks right, I'll take it! I will revisit my searches again for more info on your serpentine set up but qtek said 4.0 and 2.5 are the same balancer. I did find crown # 3242886 is listed for both 2.5 and 4.2 motors 1981 to 1993, it has the shoulder on the back like yours appears to in the photos. I did run across mention that the alignment is off by 3/8 inch when using 4.0 pulleys , it could have to do with the shoulder being on the front or back of the pulley. How confusing it all is! Perhaps this info will be of use to others when all is said and done. I also found a dorman part (double v) that looks correct but it's listed for chevy , guess it will take finding all of the measurements ( id, od, offset, etc) to see if it will work on the 2.5 jeep motor. Yes sir, I hope it helps others as well since 86 info seems very limited and if that GM pulley is cheap I'd try it or at least try to get a GM list of vehicle applications and find it in the junkyard on the cheap for trial fittament. Make sure to repost your findings here since there are always more watching in the shadows than posting. Link to comment Share on other sites More sharing options...
Eagle Posted March 8, 2019 Share Posted March 8, 2019 2.5L damper ==> J324 2886 4.0L damper ==> 3300 2920 These are from the 1987-1990 Jeep parts manual Link to comment Share on other sites More sharing options...
Shortbusdriver Posted March 9, 2019 Author Share Posted March 9, 2019 Thanks for the part numbers!, those help to eliminate the 4.0 from the equation although some other parts appear to interchange, Does the manual list the 4.2 balancer as being the same part number as the 2.5? I am curious about that since I've found at least two retail sources that claim they are. What I'm having a hard time with is finding a double v belt style, the serpentine style is all that I have been seeing in my search. It may take some time to get all of the info sorted out but in the end may prove valuable to others that are trying to preserve an older jeep, and maybe save a little frustration for them as well! At this point I am going to get the one from saveevryjp1998 and keep looking for a new replacement part, worst case is that I can have the bad one rebuilt and not have to have the mj out of service for a week or more. I will update as I find things out. Link to comment Share on other sites More sharing options...
Jeep Driver Posted March 9, 2019 Share Posted March 9, 2019 https://www.summitracing.com/parts/rnb-594-031?seid=srese1&cm_mmc=pla-google-_-shopping-_-srese1-_-dorman&gclid=CjwKCAiAwojkBRBbEiwAeRcJZFp7cCucEbSEyK4a7ew6AS87aBmvjb4If2JPSxmFSeJN64MZxCyGQRoCPeUQAvD_BwE Link to comment Share on other sites More sharing options...
Shortbusdriver Posted March 9, 2019 Author Share Posted March 9, 2019 Thanks jeep driver, that is the pulley that I found that was listed for chevys, I'm going to order one from the locale parts store and compare it to the one I remove from the mj.if it's not the same it can be sent back at no cost. I called dorman and they claimed it won't fit but I'm sorta skeptical about customer service types and I saw a listing for jcwhitney that listed it as fitting the 2.5 jeep motor- it's worth checking out. Link to comment Share on other sites More sharing options...
Eagle Posted March 9, 2019 Share Posted March 9, 2019 Keep in mind that AMC/Jeep/Eagle for a time used the Pontiac Iron Duke 2.5L 4-banger in the Eagle. That has caused a LOT of people to believe absolutely that all Jeep 2.5L engines are the Iron Duke. Link to comment Share on other sites More sharing options...
Eagle Posted March 9, 2019 Share Posted March 9, 2019 5 hours ago, Shortbusdriver said: Thanks for the part numbers!, those help to eliminate the 4.0 from the equation although some other parts appear to interchange, Does the manual list the 4.2 balancer as being the same part number as the 2.5? I am curious about that since I've found at least two retail sources that claim they are. I was looking in the 1987-1990 parts catalog. Interestingly, there's a different part number for the 2.5L damper in the Wrangler YJ. That part number is J324 2885 ... the damper for the 2.5L in the XJ/MJ is J324 2886. The damper for the 4.0L is 3300 2920. The damper for the 4.2L is J323 7196 with the V-belt pulley, and J323 7723 with the serpentine belt. Link to comment Share on other sites More sharing options...
saveevryjp1998 Posted March 9, 2019 Share Posted March 9, 2019 3 hours ago, Eagle said: I was looking in the 1987-1990 parts catalog. Interestingly, there's a different part number for the 2.5L damper in the Wrangler YJ. That part number is J324 2885 ... the damper for the 2.5L in the XJ/MJ is J324 2886. The damper for the 4.0L is 3300 2920. The damper for the 4.2L is J323 7196 with the V-belt pulley, and J323 7723 with the serpentine belt. Now you see the frustration for 2.5 guys. The best part is the 86 2.5 is a whole separate breed over the 87-90 2.5. Accessory setups with pulleys etc., the 86 2.5 is like the land of the lost for web info. I'm sure it's out there just not under mj listings. This is even more cause for me to like it from the small challenges to face. Link to comment Share on other sites More sharing options...
Eagle Posted March 9, 2019 Share Posted March 9, 2019 3 hours ago, saveevryjp1998 said: Now you see the frustration for 2.5 guys. The best part is the 86 2.5 is a whole separate breed over the 87-90 2.5. Accessory setups with pulleys etc., the 86 2.5 is like the land of the lost for web info. I'm sure it's out there just not under mj listings. This is even more cause for me to like it from the small challenges to face. From the 1986 Jeep parts catalog: There are two dampers listed. J324 2885 is the damper for 1983-1986 without serpentine belt. J324 2857 is for 1983 with serpentine belt. J324 2886 is for 1984-1986 with serpentine belt. For the GM 4-cylinder (used 1981-1983): J813 2264 So ... nowhere does the Jeep 2.5L damper cross with either the GM 4-cylinder engine or the Jeep 4.2L engine. Link to comment Share on other sites More sharing options...
Jeep Driver Posted March 9, 2019 Share Posted March 9, 2019 46 minutes ago, Eagle said: From the 1986 Jeep parts catalog: There are two dampers listed. J324 2885 is the damper for 1983-1986 without serpentine belt. J324 2857 is for 1983 with serpentine belt. J324 2886 is for 1984-1986 with serpentine belt. For the GM 4-cylinder (used 1981-1983): J813 2264 So ... nowhere does the Jeep 2.5L damper cross with either the GM 4-cylinder engine or the Jeep 4.2L engine. It wouldn't, why would you expect it to? XJ/MJ never used the GM 4cyl. XJ/MJ did use the GM V6 which the Dorman pulley I linked to does cross to. Since the V6 and early 2.5 used GM alts and PS pumps.........I suspect they used the same balancers. 90% chance that balancer will fit. Link to comment Share on other sites More sharing options...
Jeep Driver Posted March 9, 2019 Share Posted March 9, 2019 OP, just be aware that the 2.5 came with two water pumps, the most common for the serpentine was CCW, yours will be the least common so make certain you get the right one. Link to comment Share on other sites More sharing options...
JMO413 Posted March 9, 2019 Share Posted March 9, 2019 So I looked in StarParts and the J3242885 shows to go from 84 to 93 in the YJ. If you look up a Dorman balancer for a YJ it shows 2. With or without serp belt. DOR594-137 is w/o. Hope this helps. Link to comment Share on other sites More sharing options...
saveevryjp1998 Posted March 9, 2019 Share Posted March 9, 2019 All this info is helpful guys. I myself appreciate it. It at least gives people like us a starting point for trial and error. Link to comment Share on other sites More sharing options...
Jeep Driver Posted March 9, 2019 Share Posted March 9, 2019 27 minutes ago, JMO413 said: So I looked in StarParts and the J3242885 shows to go from 84 to 93 in the YJ. If you look up a Dorman balancer for a YJ it shows 2. With or without serp belt. DOR594-137 is w/o. Hope this helps. Can you just post a link? Link to comment Share on other sites More sharing options...
JMO413 Posted March 9, 2019 Share Posted March 9, 2019 https://www.oreillyauto.com/detail/b/dorman-oe-solutions-3387/engine-parts---mounts-16774/harmonic-balancer-12131/62c82173a71f/dorman-oe-solutions-harmonic-balancer/594137/6050044/1992/jeep/wrangler?q=Harmonic+Balancer&pos=1 Link to comment Share on other sites More sharing options...
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