Building Burtz block

[Gene F]

Get the o-ring main bolts.

O-ring main bolts... Where to get them? These are just drop in parts? I have never heard of these, but sound like a decent idea.

 

[alexiskai]

O-ring main bolts... Where to get them? These are just drop in parts? I have never heard of these, but sound like a decent idea.

They are sold by Burtz and are specifically for the Burtz engine.

 

[Benson]

In case anyone thinks this is a good thing, the height of the lifter has no effect on performance because the total length of the lifter + valve lash + length of the valve must be a fixed quantity. If you substitute a longer lifter without changing anything else, your valve lash will be inadequate and you'll have to grind down the valve or adjust the lifter.

I never said anything about performance!

I never said anything about anything being good or bad.

Just stated the facts.

If you mix Original A and Original B camshafts and/or Original A and Original B lifters the result is damage of cam and lifters. The exhaust valve lash on Original B camshafts is larger by 0.007 also.

 

[ModelA29]

O-ring main bolts... Where to get them? These are just drop in parts? I have never heard of these, but sound like a decent idea.

They are a Burtz part. They cut a groove in the main stud and install an o ring. He also make some tools to make assembly easier.
https://burtzblock.com/products/additional-parts

 

[gdmn852]

Grinding valves now .

 

[ModelA29]

Grinding valves now .

Lapping???

 

[gdmn852]

Yes Burtz recommended.077 for width,older engine I worked on recommended 1/16 of and inch.0625 so quite close in size .

 

[Chris Haynes]

Have ordered a Burtz cam and valves for engine, still trying to decide the cam followers , single lock or double, might go with single due to larger base .Just cleaning and de burring so far.

Use the COLONY brand lifters.
www.colonymachine.com
You have to ask for them as all that is in their catalog is Harley-Davidson parts.

 

[gdmn852]

Picture of o ring bolts

 

[Bruce of MN]

I'm sure Terry has looked into it, but ordinarily, a notch like that is a stress raiser and is something to avoid.

 

[JayJay]

I'm sure Terry has looked into it, but ordinarily, a notch like that is a stress raiser and is something to avoid.

I installed the O-ring bolts in my Burtz and they haven't snapped yet.

Having said that, I don't recall whether they are cut flat-bottom or curved bottom. The stress riser would concentrate on the sharp edge of the bottom of the cut. Typically O-ring grooves are cut flat bottom to give the rubber space to migrate under compression.

 

[ModelA29]

I'm sure Terry has looked into it, but ordinarily, a notch like that is a stress raiser and is something to avoid.

Also my concern. They do appear to be sharp cornered but still leaving as much meat as the smaller part of the stud.

 

[Bruce of MN]

Sharp corners bad was one practical thing I learned while getting my mech engr degree.

 

[CWPASADENA]

I installed the O-ring bolts in my Burtz and they haven't snapped yet.

Having said that, I don't recall whether they are cut flat-bottom or curved bottom. The stress riser would concentrate on the sharp edge of the bottom of the cut. Typically O-ring grooves are cut flat bottom to give the rubber space to migrate under compression.

Having assembled 25 Burtz engines early on, I machined the "O" ring groves myself before Terry was offering bolts with the groves. I always machined the groves with radiused bottoms. The square groves are definitely a stress riser.

Chris W.

 

[Lawrie]

you really dont need the grooves,if you make an installer so,the o ring doesn't get cut slipping it inpast the main bearing bore it will sel on the small diameter of the stud and oil pressure will push it up to the taper part of the stud, and there it will stay.
lawrie

 

[dlshady]

you really dont need the grooves,if you make an installer so,the o ring doesn't get cut slipping it inpast the main bearing bore it will sel on the small diameter of the stud and oil pressure will push it up to the taper part of the stud, and there it will stay.
lawrie

I just finished assembling one for a customer and what I did was to use the larger O-rings which were spec'd out in the earlier builder's guide that seal on the smaller diameter of the stud, as you mentioned. I wiped a ring of RTV around the smaller diameter, inserted the stud and then took a piece of .001" brass shim stock to guide the O-ring in without cutting it and inserted a couple O-rings on each stud. Then I took a piece of the correct diameter tube (also spec'd in the earlier builder's guide) and pushed the O-rings down into the RTV which made everything seal up perfectly. The key is to work quickly and get everything into place before the RTV sets up. I got everything torqued down and let the RTV set up overnight, then I came back and plastigauged the bearings. So far, not a single leak!

 

[gdmn852]

Hello, took a ride to Snyders and picked up parts . The lifters are Colony manufactured,as recommended in previous posts.

 

[gdmn852]

Hello , Dodge tryed to pm didn’t go through, please explain more. Thank you.

 

[ModelA29]

Hello, took a ride to Snyders and picked up parts ..

Must be nice - 4,800 mile round trip from here. Shipping or driving takes about the same time to get the parts.

 

[gdmn852]

I live near Erie ,Pa … let that place be avoided until grass grows in its streets…. 1853 Horace Greeley , about 2 hours away ,but any how got back working on Burtz , installed cam and valve train .