1975 135HP intake manifold bolts

[Randyg123]

This is one of those, "how the %$!$ did I miss" this categories.

Please look at the attached photo. I just realized that I have a bolt missing on my intake manifold. Right where I put the red dot. To the starboard, there is the timing pointer. To the port, a screw.

Is this supposed to have the same bolt that is in the other holes? Becuase I tried to put one in there and it is too small.

The manual says there are ten bolts to remove and BRP's site shows eight in the price list Part number 22 in the photo. Does a different size go in this hole?
If so, what size is it is it Part number 23 in the same photo which is just identified as a longer bolt. Do you know what length it is and is it the same diameter?

I just can't see how I missed this. I am losing it!!!!!

Thanks,
Randy

 

[emdsapmgr]

Re: 1975 135HP intake manifold bolts

The missing part is not a bolt, but probably a screw. The phillips head-type screw holds the top of the reed box to the back side of the intake manifold. Some these same screws hide under the carbs, others are visible elswhere on the mainfold face. If the screw is loose, that reed box may be "loose" and you you may lose some crankcase compression on that cylinder. It is possible that you may get a little compression spit back through the carb throat. Best case, you may be able to thread in the correct screw, catch the hole in the reed box and fix the problem. Worst case, you'll have to remove the intake manifold to re-position it.

 

[Randyg123]

Re: 1975 135HP intake manifold bolts

I don't think it was a screw because there is a screw right next to it on top of the 'hump' on the starboard side.
I think this is the screw you are referring to because the drawing I provided is misleading you. It doesn't actually show the bolt hole I am referring to because from that angle of the drawing the bolt hole is behind the timing bracket molded into the manifold.
The bolt hole butts up against the port side of this bracket. Plus I can see evidence of a 'star' lock-washer pressed into the metal around the hole.

I was in a hurry an just had a minute or two to edit that drawing and I did a poor job.

So with this information, do you still think it was one of those screws? I'm hopoing it was just one of the two 'long' bolts. I just can't find a description of the length or diameter. Guessing it is 1/4" x 1.5"

 

[ezeke]

Re: 1975 135HP intake manifold bolts

You should have 8 part # 302288 and 2 Part # 306493 shown as #22 and #23 on the diagram.

If you look at the gasket, you can see where screws are needed.

 

[Randyg123]

Re: 1975 135HP intake manifold bolts

You should have 8 part # 302288 and 2 Part # 306493 shown as #22 and #23 on the diagram.

If you look at the gasket, you can see where screws are needed.

Just got my manual and boat and me all in the same location at the same time. Busy day!!! According to the manual, it is a boat hole but there is no distinction on which takes a long bolt or short bolt that I can find. The two #23's go somewhere. I looked at the manual and this is for sure a bolt hole as my drawing location was deceiving to you all.

I assume it is a 1/4" bolt but have no idea on the length. If you look at the part description, they give overall dimensions (i.e. they include the head size in the dimensions). Ity looks like, by shining a light down into the hole that a bolt stripped out in it. No doubt someone put a poor-quality bolt in this hole as I found in another (the one I broke). I tried to screw a 1/4" grade 8 bolt into the hole but it won't start well. slight CW twist and back out pulls pieces of metal. I don't think I am stripping the hole, I think I am cleaning pieces of the soft bolt out of the threads. Not sure, I may have to get a tap to clean it out. Or maybe just cut a notch into the bolt i have now.

Is this a 1/4" 20-thread hole?

It's this shade-tree mechanic type stuff that really has me worried what I could find elsewhere.....uughh!!

 

[R.Johnson]

Re: 1975 135HP intake manifold bolts

That is a 1 inch long, 10-24 phillips head screw. It hold's the upper most reed box to #1 cylinder. That reed box must have a gasket, and pulled down tight for a air tight seal.

 

[Randyg123]

Re: 1975 135HP intake manifold bolts

That's two votes for it being a screw. But I am still not sure because my drawing I felt was misleading so now I have a photo to offer.

Please note the arrow in the photo pointing to the location of the missing bolt/screw. Do you still think this is a 10-24 screw missing?

 

[R.Johnson]

Re: 1975 135HP intake manifold bolts

The screw I'm talking about is just to the right of that hole. That hole is for a manifold bolt.

 

[R.Johnson]

Re: 1975 135HP intake manifold bolts

There are 8 short bolt's, and 2 long bolts.

 

[Randyg123]

Re: 1975 135HP intake manifold bolts

Aye aye, I think it is definitely a long-bolt situation. I bought a 1.5" 1/4" 20 thread bolt but it will not go in and I did not want to force it until i was sure it was supposed to be the 1/4" bolt. Okay...I don't really mean force it but I am going to use a tap to clean out the threads.

Last time I mention using some force Mr. iwombat got upset and was worried about having nightmares over it. I don't want anyone too loose any sleep

Last question, I promise (untile my next one). Some of the manifold bolts have lock washers on them but that is not called for in the parts catelogue. Should I remove those an just use the bolts alone? I think I will replace all of the bolts just to be sure.

 

[R.Johnson]

Re: 1975 135HP intake manifold bolts

The two long bolts are 1 1/2", 1/4-20

 

[Randyg123]

Re: 1975 135HP intake manifold bolts

Thanks for the input, will tap out the hole today to clean threads and see how a new 1.5" bolt goes in. New intake gaskert comes in next week, I hope.

Back to an earlier question. Some of these bolts now have lock washers on them. When I put this back together, should I still use them or toss 'em?

Also, is the torque for these just the standard 1/4" torque of 60-80 in-lbs?? Seems a bit light.

 

[Randyg123]

Re: 1975 135HP intake manifold bolts

Bump ^^ revised my question