Intake Manifold Bolt Broken

GoldenMotor.com

jMrL

New Member
Feb 25, 2016
68
0
0
Norfolk
Well I was tighting everything down and a snug turn of the manifold nut broke right off. I was like NOOO, tears went down my face, my heart skipped a beat, I fail to my knees, and prayed to the bike gods...

Now I need a bolt, after searching local stores and to no prevail I am here and looking for a reputable source to purchase this part, possibly FAST! :D What size do I need? What length do i need?
I can just use a pair of pliers to get this bad boy out yes?
ALL HELP IS Greatfully appreciated!

Here is some heart breaking, pictures brought to you by the one his self, The Torn individual that is wanting to ride with the kings but yet again!


 

2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
It is 6mm X 1 thread. Length will have to be determined but probably about 16 mm.
Instead of replacing it with a stud and nut you can use an Allen head cap screw of the same size/length.

While you're at it, replace the other one as well as the ones in the exhaust manifold.

Now is a good time to buy a torque wrench. Those fasteners don't need any more than about 60 inch pounds. Overtightening is a common problem with these engines and why we stress the use of a torque wrench.

Tom
 

jMrL

New Member
Feb 25, 2016
68
0
0
Norfolk
Thanks 2door, I went ahead and ordered 4 studs, for the exhaust and the intake. I did it before reading your post, Not thinking of the Allen screw. That would have been alot easier and less likely to break, strip and more. Duly noted, and the torque wrench is a must I know. I bought a gasket for my exhaust and manifold also. Hoping this will help the leak i have on the exhaust. I cant seem to get rit of it for nothing. I had a small leak coming from the head and i loosened the screws and snugged them down and it removed that one. I have tried flipping the gasket and everything on the exhaust to no prevail.
 

jMrL

New Member
Feb 25, 2016
68
0
0
Norfolk
What is something good to put around my seals. Ive seen some pics of extra sealent on the exhaust, manifold and such. Such as a epoxy.
 

2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
You might want to consider 'lapping' the exhaust manifold flange at the gasket surface. They are usually warped from the factory due to the welding process.

By 'lapping' I mean clean the gasket surface and 'paint' it with a magic marker or machinist die. Run it over a sheet of sandpaper affixed to a known flat surface (glass woks good) and you'll quickly see the high and low areas that need to be sanded or ground flat. The same procedure should be applied to the intake manifold where it attaches to the cylinder. Also the kit supplied gaskets are typically of questionable quality and you'll be better off making new gaskets from a good automotive quality gasket material available at most any auto parts store.

The intake gasket can be thin, 1/16 to 3/32" thick but make your exhaust gasket from material at least 1/8" thick and from material made to take the heat of exhaust. Once you have a good, flat gasket surface and quality gaskets you'll have no need of gasket sealing compound. Just tighten the fasteners to the above recommended torque values and recheck them after a couple of heat/cool cycles and you should be good to go. Also most silicone gasket sealers are not compatible with gasoline. Read the labels

Tom
 
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jMrL

New Member
Feb 25, 2016
68
0
0
Norfolk
It is 6mm X 1 thread. Length will have to be determined but probably about 16 mm.
Instead of replacing it with a stud and nut you can use an Allen head cap screw of the same size/length.

While you're at it, replace the other one as well as the ones in the exhaust manifold.

Now is a good time to buy a torque wrench. Those fasteners don't need any more than about 60 inch pounds. Overtightening is a common problem with these engines and why we stress the use of a torque wrench.

Tom
Just broke down and bought a torque wrench , I seen harbor freight was having a leap day sale 20% off. So i got one for 20$ shipped. Couldn't beat it. Might not be the best! but It will suffice until i can spend more cash on the tools. Im lucky to have some of the things i have now. Grinding it at yard sales and such.

TO deal with your other post. I just went outside and used "rescue tape" and wrapped it around the exhaust a few times at angles, I started it up and ran it down the street to test for leaks and to my surpise it worked really well. I bought this tape to modify my exhaust by cutting it in half and using wire housing to insert into both ends that ive cut and wrap it with the rescue tape " silicone based tape " That is something im going to do at a later date once i get everything done pat, So i dont have to keep adjusting things to change something else.

I REALLY appreciate your responses, I am a young mechanic " experience wise " and just taking each thing i do a step at a time trying to learn as i go. People like you i really look up too because you are willing to give advice.
 
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2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
jMrL,

The reason this forum was established was to offer help and advice to the new builder and to get them on the road with the least problems. We want you to enjoy your motorized bicycle and any offer of help you need we'll gladly offer.

Never hesitate to ask because there is no such thing as a dumb question or one to elementary to answer. We all started at the bottom. :)

Have fun and ride safe.

Tom
 

MEASURE TWICE

Well-Known Member
Jul 13, 2010
2,770
1,267
113
CA
I bought a torque wrench from HF and so far it has been fine. In the past I've made a mistake when I did not see in a manual torque listed for a specific location on the product I was working on.

I took the markings on the head of the bolt. Some have a marking or tick marks or something.

Then I found out later is just the max the fastener can handle as a specification. I did not break anything. I suspect for some time now I probably ought to have the torque wrench for lighter torquing valves also.

Mostly I use the foot pounds (think goes to max 130 about), for the 100ft/lbs to torque the lug nuts on vehicle using the even star pattern sequence of tightening. I do hand tight first, followed by torque wrench at 30, then 60, then 100. I like to be sure it is flush and not warped and not liable to come off.

I just got another mailing for a 20 percent off I may use to get the other torque wrench. I have adapters to take the 1/2 inch drive down, but the handle on the bigger torque wrench in some situations is a bit much to steady.
 
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Cylon

Member
Jun 26, 2015
346
9
18
Maine
Just as a future reference to you and anyone else that finds this thread looking for what bolt fits, go to lowes and buy the hillman button head Allen cap screw and its a m6-1.00x16 also get some steel washers and lock washers. All the hardware should be replaced with high quality american steel. You will find less things breaking, loosing and stripping. UPC is 0 38902 03317 8 with that number all a sale associate has to do is look it up in the computer and they can find it for you.
 
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curtisfox

Well-Known Member
Dec 29, 2008
6,074
4,035
113
minesota
Also anyone with a broken bolt can take it to, like Lowes or Ace Hardware they have tread gages and can check the thread for the right size. Auto parts stores also, then you can pick them up right there..........................Curt