Turbo Dodge Forums banner
1 - 20 of 24 Posts

·
Registered
Joined
·
25 Posts
Discussion Starter · #1 ·
I posted before about my 93 iroc rt, the brand new high flow oil pump and Ishaft
are stripped again after 5 miles of replacing them, and i cant figure out why it keeps doing it. Can some please provide me with all the information on this, anything anyone can to do to help me figure out what the problem could be.
 

·
Registered
Joined
·
4,910 Posts
What are you tensioning the belts too? How are the shaft bearings? Thats kinda odd, and quick.
 

·
Registered
Joined
·
25 Posts
Discussion Starter · #3 ·
See thats the problem i had a shop do it. and he has worked on this engine and he cant figure out why either what is the tension it should be. and should it strip out that fast?
 

·
Registered
Joined
·
4,910 Posts
Tension needs to be 80lbs. That is way quick for anything to strip out. Has he checked the I shaft bearings?
 

·
Registered
Joined
·
1,000 Posts
I set mine to 95 lbs per Jackson and Rick D. No problems after numerous 7000 rpm pulls. Your mechanic needs to set this tension with the proper gauge!!!!!!! If you don't have one - get one.
 

·
Registered
Joined
·
4,910 Posts
95 is correct. My bad. And I couldnt tell you how loose or tight would cause problems. But they both are bad.
 
G

·
To low of belt tension causes alot of deflection oat the run between the intake cam and the I-shaft. Having it too loose will eventually strip out the I-shaft/oil pump teeth. I have seen it too many times an eveytime that is what has been the problem. Having the belt too tight will eventually burn out the I-shaft bearings. I have found that 95Ft/LBs is the "sweet spot" The FSM states that tension should be 110 for a new belt and I did so on a new motor with new bearings and it had to come apart a few hundred miles later(oops, too much boost) and I saw the same wear on the 10 o'clock position on the bearings as if it were too tight. I put another motor together with new bearings and checked after about 1000 miles at 95LBS and they looked brand new. At 110LBS the belt actually sounds like its too tight.

So if I were you I would install some new bearings and set the tension to 95LBS and report back as to how it does:thumb:
 

·
Registered
Joined
·
25 Posts
Discussion Starter · #11 ·
He said he didnt know what tension it was at, he just said that it was tight. wtf? the engine had been rebuit 30,000 miles ago before i got it, if any parts were machined wrong could that affect anything?
 

·
Registered
Joined
·
670 Posts
He said he didnt know what tension it was at, he just said that it was tight. wtf?
This alone tells me the mechanic is a complete ignorant incompetent moron. You're best taking the car to someone else who knows what they're doing. I've installed the timing belt on this motor to "what I thought was tight" and then measured the tension with a proper timing belt tension guage, and it was WAY over 110 lbs (thankfully, I never ran the motor like this :eek: ). Tighening the timing belt tensioner can put the tension on the belt higher than one would think.

As far as the other parts that were machined during the rebuild, it depends on how long the motor was run after the oil pump stopped turning.
 

·
Registered
Joined
·
25 Posts
Discussion Starter · #13 ·
I just want to make sure before i have new parts put in, and ill make sure its got the right tension. The pump broke on my first drive with the car, i shut it off right away
 

·
Registered
Joined
·
670 Posts
The pump broke on my first drive with the car, i shut it off right away
If such is the case and you didn't hear any noises coming from the engine other than the pump failing, you should be fine, but you should pull the rod and main caps off and check the bearings for scoring before you continue.
 

·
RIP
Joined
·
1,363 Posts
Search on ebay for "Belt Gauge" their are usually a couple on there for $20 to $80. Even the ones with the side extensions will work fine. I have one of both.
 

·
Registered
Joined
·
25 Posts
Discussion Starter · #17 ·
I think that the bushings are bad cause the way its stripped is on the end ill post pics here soon. My setup was a brand new stock i-shaft and a melling high volume pump. What would be the best setup be?
 

·
Registered
Joined
·
4,693 Posts
I'd recommend a stock Mopar oil pump. You really don't need the high volume oil pump, especially when the TIII I-shaft sprocket is already smaller (overdriven). A non-HV oil pump should impart less stress on the helical gear.
 

·
Registered
Joined
·
25 Posts
Discussion Starter · #19 ·
So ill go with the Cyro Treated I-shaft and the stock mopar oil pump and the new bushings, ill set the tension on the belt to 95? sound good?
 
1 - 20 of 24 Posts
Top