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Hello, I'm installing a JEGS mini starter to replace the no brand mini-starter that burned out. The block is from a '74, fitted with a 153T flywheel and a 4SP manual. If you look at photo 1 you can see that that two of the three mounting bolt holes in the block have a 1/4" shoulder before the threaded portion begins. The hole nearest the flywheel is threaded flush to the lower face of the block. The knurled portion of the starter bolt body extends about 1/4" above the top face of the starter (pic 2) and engages in that shoulder area. This starter only uses the two forward-most bolt holes in pic 1. One bolt will fit ok but the other stops prematurely when the knurl hits the thread. The previous starter fitted ok because the mounting face is about 1/4" taller than the JEGS version. Does anyone know the right way to fix this?
Thanks in advance.
Can't you just "machine" the few thread needed to clear the knurled part of the bolt. Is there enough threads in the hole to do that and still hold good?
Can't you just "machine" the few thread needed to clear the knurled part of the bolt. Is there enough threads in the hole to do that and still hold good?
Yes, I believe there is enough thread remaining. I can either grind some knurl off the bolt or drill out the first portion of the hole but that feel like a bit of a "hack". Wondering if there is more of an out of the box solution.
Never use common shank bolts. Starter bolts are special to keep things from shifting during the huge torque events of cranking.
I have a bad feeling about bubba stacking washers.
I would not drill that block either.
I wonder if a Fasten-All is nearby. Or, better yet, see if ARP has an on-line catalog.
I have their paper catalog, almost a half inch think. Truly amazing how many bolts they make.
Their web site may have a search box for knurled Starter Bolts.
Just need diameter, TPI and the length YOU want.
If the threads in the block are deep enough to accept the current bolt thread length, why not get a reamer and cut the counter bore deeper to accept these bolts. That knurl on the sidewall of the bore seems beneficial to maintaining starter location.
There is always the possibility the manufacturer just simply gave you the wrong bolts.
Who knows? Maybe they fit BBC or LS. Or fits one of their dozens of other starter models.
Anything can happen with new employees packaging products.
I sure wouldn't make alterations on my engine block to fix somebody else's mistake.
Find the right hardware or ship the starter back.
They will take returns whenever a part does not fit.
i had to use 3/8” aluminum spacers on my knurled starter bolts. No problem and that was 10 years ago.
still working great.
Did the spacer prevent the knurled part from protruding into the bolt hole in the block? How high a spacer did you need to use? I will need to use at least 1/4". You've had no discernible movement of the starter not having the knurling protrude into the block?
There is always the possibility the manufacturer just simply gave you the wrong bolts.
Who knows? Maybe they fit BBC or LS. Or fits one of their dozens of other starter models.
Anything can happen with new employees packaging products.
I sure wouldn't make alterations on my engine block to fix somebody else's mistake.
Find the right hardware or ship the starter back.
They will take returns whenever a part does not fit.
I'm certain the bolts are right. The more I dig I'm realizing that the issue is that the block is drilled for a staggered bolt pattern which implies the intended flywheel is a 168T. However the previous owner for some reason known only to them installed a 153T. The problem is that you can't buy a staggered starter in the 153T configuration they are straight. So, I'm trying to make this work with the least amount of "dodgy" adaptation possible in consideration of the possible next owner. Agree on not modifying the block. I think at this stage I will either use a non-knurled bolt or pack the correct knurled bolt with washers to make it fit. I bellieve I can get away with two. I feel bad doing something like that because it doesn't seem like a professional repair but I'm not about to swap the flywheel to make a staggered starter fit.
I just checked ARP web site. Enter starter bolts.
Very easy to navigate. For a SBC they want to know dia, TPI and Under-head Length UHL.
I do not have that information. Check it out.
They come in 4.6", 4.7" 4.3" UHL if that helps any.
Why not use a washer?
In fact, for the starter alignment with the flywheel teeth, aren’t spacer/shims provided by the manufacturer to move the starter in and out until correct? Those shims slide in between the starter and block which, in effect, does the same thing to the bolt depth as a washer between bolt head and starter body.
For those following I decided to fix this problem by adding 1/4" of additional threading to one of the new bolts that came with the starter using a 3/8 -16 die. This gives me some knurling to do its job while also fitting in the bolt hole that is threaded flush to the face of the block. The original is on the left and the modified on the right. Seems to work just fine and its a "hack" I can live with
I think it's a helicoiled bolt hole. It's not stock. Look closely at the picture.
Tighten it up with the starter in place....measure twice....grind the bolt shoulder to suit. Bubba was here!!!
Its not heli-coiled what you're seeing is some thread damage caused by the previous owner trying to overtighten the knurled bolt and damaging the thread. I cleaned it with a 3/8 - 16 tap and it's ok. I think that bolt pattern is standard on manuals with a 186T flywheel. The knurled bolts fit in the staggered positions and a normally threaded bolt goes in the fully threaded hole. MY problem is that I don't have a staggered starter because I have a 153T flywheel.
Starter motor bolt issue
