whatsav8

Hi everyone,

So I'm in the process of putting my head back together on my X. The front bearing cap (4 bolts) closest to the cam sprocket, are giving me issues when trying to torque them to spec. I've checked about 20 different times to confirm the spec of 22 ft/lb on all 4 of the bolts. I kept everything in order during the tear down, so nothing has changed come re-assembly. The bearing underneath the front bearing cap is properly placed, and it is sitting flush on the head..

So long story short, you are supposed to be able to tighten down the 4 bolts to 13ft/lbs the first pass, and then 22ft/lbs the second pass. I can't seem to get the bolts torqued past 19ft/lbs? I came damn close to breaking all 3 bolts off. All they are doing is spinning..wtf? In my eyes I have tried everything.. i'm following the manual and guides for the torquing order as well. Even torquing in like 5-6 small intervals up to 22ft/ lbs makes no difference..

Has this happened to anybody else? Or any other ideas as to what I can be doing wrong? Any help is appreciated.. thanks.

4b11slayer

Just stop there. Before you shear the bolts. I know everyrhing has a torque spec. But aluminum isnt very forgiving. I just go by feel. Over the years your wrist becomes a torque wrench. Lol

They aint coming loose. If it were a head bolt or rod cap or main cap id lose sleep but not the cam caps.

whatsav8

Lol alright, I just torqued to 19 ft/lbs and called it good. Thanks

One other question.. Would you/anybody be able to help me out with valve lash and tell me what I am doing wrong here? I am using the "4B11-SHIM-CALC" spreadsheet (found on here) to help me figure the cam buckets in which side I needed to order. So I did this last week, got the new cam buckets, installed them, and noticed cylinder 1 Exhaust is measuring 0.015 instead of the specified 0.012. However, it appears the other valves I have checked are within tolerance. So I figured I must be doing something right here...

Correct me if I am making a mistake. I am using the equation specified in the owners manual and comparing it to the 4B11 SHIM-CALC sheet (attached)

Intake valve: A=B+[C-0.20mm (0.008 inch)]
Exhaust valve: A=B+[C-0.30mm (0.012 inch)]

A= New bucket to order
B=thickness of current bucket
C= measured valve clearance

I converted everything to thousandths for myself and used a micrometer. For instance I have a 3.180 bucket (0.126 in thickness) and a .008 measured valve clearance. So I went..

0.126+[0.008-0.012]=0.122 and compared it to the chart. It says I need a 3.000 bucket, right? But obviously i'm wrong, or the chart is wrong. I don't have "c micrometer" to get mm, but I am assuming my method should work fine. Any help is much appreciated!

Here is the chart: https://www.evolutionm.net/forums/ev...alc-chart.html

LetsGetThisDone

iTrader: (1)

You should go get your torque wrench calibrated. I've torqued those bolts to 22ftlbs several times without issue. They may be over torqued even at what you currently think is "only" 19ftlbs.

whatsav8

I've used 3 torque wrenches, re-tapped the threads, and bought higher strength bolts from the hardware store. I've tried going in increments of 5lbs, 3lbs, etc. in the proper order and I can still not torque past 19lbs on either torque wrench. I can totally see your point if I didn't have access to multiple torque wrenches. I'm not sure what else to do lol.. there is nothing else I can do. It doesn't make any sense..

►EvolutionX◄

iTrader: (2)

I’ve had a brand new out of the box torque wrench snap head bolts, then immediately after be tested for calibration and have no issues. I don’t trust torque wrenches unless I have to, because I’ve learned from situations such as yours not to. Rely on your tactile feel in combination with the wrench. Tighten them down tight and just re check them after a few drives

►EvolutionX◄

iTrader: (2)

Also, if you’ve re-tapped the threads they are weakened and may not hold up to the 19 ft-lbs they are supposed to, and you may be better off using a inch-lb wrench or manual torque wrench

LetsGetThisDone

iTrader: (1)

If you ran a tap through them, and not a thread chaser, you weakened the threads..

ossimbrian

Unless you have oil or other fluids filled up in those holes while tightening, tight is tight man, its not coming undone.