bent pushrod

[clunker1]

Had a delay in my project and just got back to it. I installed a .450 lift cam with stock refurbished heads. In my haste, I assumed stock heads, valves and collars would not have an issue with .450 lift. I put the pushrods in and rolled it over. It bent a pushrod. Pulled the head and took a bunch of demensions on the valve and spring (like I should have in the beginning). I only have .400 travel available before the top collar hits the valve guide. I checked the spring installed height and found it to be 1.25" (not spec of 1-3/8"). The dimension from the top of the valve guide flange (against the head) and the top of the valve stem is 1.435 (not 1.5").

I am not sure how critical the spring installed height is. Also, I was wondering if I could cut down a little on the collars but there is not much extra meat to start with. Could I machine lower collars that sit closer to the head (instead of the stock stand-off)? If so, would regular cold rolled carbon steel suffice?

Any other ideas or suggestions/recommendations would certainly be appreciated.
Dennis

[nan00k]

not an expert here at all. However referring to the spec' having installed a sifton crusader with 0.440 lift in & ex on a 52 FL which for some reason meant you added an extra 0.15 to the lift it said to reduce guide length whith guides in the head, they state that spring travel to coil bind as 0.470 and free travel as 0.520 (? are they the wrong way around) . You will lose longevity, if you do not have enough trvel to spring coil bind , yes, machine off underside (not surface bearing against head) of the lower collar required to achieve necessary free travel.

All I can remember having to do was reduce length of guide and I had no prob's. All the best

[58flh]

Clunker---The spring height & pressure are very important to have a daily running bike!--I run a cam with the rocker ratio of a pan /final lift is .450.I didnt have to do anything special for that lift!---But mt valves are SUNKEN into the head to bad From previous jobs.If you have different heights Then its actually not all the spring & guides fault.If your heads are sealing good -Then the obvious fast fix would be to Face the guides some so the collars dont hit!.Another thing you should check is -(if your valves are really sunk,is --Put the cover on with gasket & roll the notor over to see if the EX. spring/collares dont hit the edge!.--Its better to find it now then when its fired!.There should also be a min. of .060 between both valves when there both open briefly during duration of the cam lift.--This would be the FIRST thing I would check!--All the others are Just a minor setback.---Respectfully---Richie

[clunker1]

Got some great advice here and from a head rebuilding specialist. I had to learn some lessons the hard way. Checked clearance from top collar and top of valve guide at full lift of cam. Guide needs to be machined down. Also checked minimum required install height for spring (in this case, fully compressed outer spring dimension + .450 lift of cam + .060" tolerance before spring bind). Using stock panhead springs, it is tough to get there. Furthermore, there is not enough spring tension at this spring installed height.

Had some higher lift shovel springs and using them, the required install height was 1.395" and need to make room for 0.140" of additional spring travel. Checked the spring tension at this required install height and have tension similar to FLH spec in manual.

My solution is to use medium lift collars to move top of spring up 0.060" and machine new lower collars to move spring bottom down 0.080". Since there is 0.100" gap from bottom collar to aluminum head, lower collar will still be supported by the valve guide as designed.

Here is my new dilemma. I checked out the stock lower collars. I do not have a hardness tester, but my guess is that this material is quite high strength and hardness. I would assume a heat treated chrome-moly like 4140 or 4340.

These alloys are a little more difficult to heat treat without a heat treat furnace and an accurate means to monitor soak temperature prior to quench. I was thinking of using a W! steel (like 1095) that is routinely hardened and quenched in blacksmith shops by monitoring heating temperature by color and magnetic property loss before quench.

any ideas???? Anyone know the actual material these lower collars are made of?
Dennis

[59Panman]

I believe mbskeam made his own push rods. You might want to check with him, as he is a member here.

[58flh]

Clunker---If your valves are sunk into the head /The valves will have to be tipped so all are the same height!/Also you can use the stock springs if there good!/If more seat pressure is needed You can Put a shim under them!--They come in .020, .030 ,.040, .050!.Which ever one will bring the pressure up to par!./& About the P-rods I recommend steel for both HYD. & Solid tappets!--Even though Alum.-COLONY p-Rods work well on HYD. tappets!-(With Stock cams).I have all the bikes in the crew on steels/Hyd. also.I just like the piece of mind!-(After collecting a shoebox half-full of Alum. P-rods--I tend to stay away from them.But I have to inform you that ALUM.-Rods work good with HYD.-tappets!.Also inspect your P-rods like this--In the middle of the rod you will see circular grooves!-(thats how much they bend in use.Then check where the bottom ADJ. is & look for the ALUM. to start bulging where the ADJ. & Alum.-rod meet!/This goes for the top insert also.Roll them on a flat surface/If they wobble EVEN SLIGHTLY--THERE not going to last!/Also Mic. the tube above the incerts about an inch///then MIC. right on the ADJ. & top ball where there inserted.IT will Mic. out MORE as the Problem is already starting its process!.---Hope this sheds some light for ya//OH yea PULL the inserts out There very good Hardened steel!--Tou can put them in used steel shovel p-rods! & save alot of cash on getting NEW P-rods!---I have both my EX. P-rods done like this & I have no worries/Also I rack Alot of miles.----Respectfully----RICHIE,--GOOD-LUCK

[clunker1]

Thanks Richie. Now that you mention it, I do have concerns about my pushrods. My valve seats in my heads are a little less than stock as far as the position of the valve. This makes the pushrod a little short also. I was thinking of getting steel tubing and re-using inserts to make my own pushrods. Any idea what tubing steel spec to get? I'll check with mbskeam as well.

Dennis

[58flh]

I sent you a PM---Richie