Viscous Diff Troubles

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MonsterAir

MonsterAir

Lone Racer 🤠
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Hey guys this is my first post on the site. Getting back into the hobby after a 5yr hiatus and can't wait to drive my Marder again. Just about got her running but having a little trouble with my viscous diff. Originally installed by the lhs, I pulled it apart and found the fin pack separated with a few on each side of the gears. Couldn't find any info about why they might have done this and of course they closed down a few months ago. Good riddens but lol now I need help...... So I found the installation guide online and per the instructions the whole fin pack should be on the left side so that's what I did. Installed and filled with 10k diff oil but now my diff is fully locked up. Won't even roll when pushed. There's about half an ounce of oil in there. One thing I did notice was it seemed to have less of a locking effect when I backed out the 2 screws that hold both half's of the diff together. Anybody have any idea's on what I should do? Maybe remove the fin pack? It's a pain cause now I gotta pull it back out again so this time I wanted to get a little educated so I don't have to do this again for a while. Any help would be greatly appreciated! Thanks.
 
Ok so I pulled the diff back out to try taking out the fin pack and now the 2 halves are stuck together! Any advise on pulling them apart? Tried heating it up, vise and a puller but won't budge. The learning curve is killing me here. Any help would be greatly appreciated as this is the last problem area before firing her up.
 
Well for those of ya that pop in to take a look. I was able to pull the 2 halves apart. A little elbow grease a few blisters, some heat and pop it came apart! Cleaned and assembled but this time I didn't tighten the screws down all the way and so far everything is working like it should. Still the question of why the lhs would split the fin pack up like that. I guess if I get no response here I'll eventually try splitting them up and see how she runs.
 
MonsterAir said:
Well for those of ya that pop in to take a look. I was able to pull the 2 halves apart. A little elbow grease a few blisters, some heat and pop it came apart! Cleaned and assembled but this time I didn't tighten the screws down all the way and so far everything is working like it should. Still the question of why the lhs would split the fin pack up like that. I guess if I get no response here I'll eventually try splitting them up and see how she runs.
Click to expand...

Sorry I didn't see this post before.If its like the one I had the set screws shouldn't be all the way in.I think I done mine 7 turns for the lock I needed.
I'm trying to find a pic of mine but looking through 1 Tb of pictures is getting a nightmare!.
Is your diff like this?
http://rc-car-online.de/homepage/content/explosionszeichnungen/teile/diff/viskose_diff.pdf

J:rolleyes:
 
running a visco in the touring car I read a few threads on several forums about setup's ect some have used extra fins so there running 6 each side but they said it was a bit aggressive

I never had a problem like yours though id double check the fins as a tiny little bend can stop it turning, the 2 screws that hold halves together on mine are done tight, it could also be the shims inside locking it up and making it tight

fg supply 1000wt oil with diff an recommend 2000-4000 as a option so 10k may be to thick I think I went with 6000 in mine
 
Yes that's the one I have. 1T is a lot of photos! I tightened the screws til they were flush with the housing. Didn't want it binding again and all seems fine so far.



AL- I don't blame ya. It's a little time consuming pulling it out and very messy with the oil. Down the line I think I'd like the one that can be set by allen key adjustment. Sounds less messy and prob don't have to pull the damn thing out to adjust.
 
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renbar said:
running a visco in the touring car I read a few threads on several forums about setup's ect some have used extra fins so there running 6 each side but they said it was a bit aggressive

I never had a problem like yours though id double check the fins as a tiny little bend can stop it turning, the 2 screws that hold halves together on mine are done tight, it could also be the shims inside locking it up and making it tight

fg supply 1000wt oil with diff an recommend 2000-4000 as a option so 10k may be to thick I think I went with 6000 in mine
Click to expand...


I am going to try running it and see how she runs. Wow i thought 10k was supposed to be real thin oil. I'll try out some lower viscosity oil too. I really need to control the wheelie action on the hole shots, got a 27.2cc ESP modded engine. Will lift the front wheels up at about 1/4-1/2 throttle pull.
 
I'm using the 500.000 oil in my viscous diff and it runs good if you ask me never had any problems. Not sure what they actually recommend to use on this difs I just went for the thick stuff straight away lol
 
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