New 4.3L Long Block has no valve restrictors or retainer installed. Are they needed?

[ccrobin]

My 1st post!

Greetings to all. I first want to thank you all here as this forum has been a great assistance to me.

I just acquired a 1987 Hurricane with the 4.3L OMC. The block was cracked (which I knew when I purchased it), so I ordered and just received my new long block from Rapido (I opted for the flat-top pistons). Engine arrived yesterday and looks great. So far so good.

I noticed on the new engine though, there are no valve restrictors or retainer installed as on the original motor. The valve design on the new motor looks different and does not appear to need them, but before I button everything up I just want to be sure. Obviously I'd have to remove all the valves to swap my old restrictors over, which seems to defeat the purpose of getting a long block.

I have searched all over but cannot find any information about this. Anyone with input would be greatly appreciated.

 

[ccrobin]

Here is a diagram of the parts I am talking about.



See item #2 and #7

 

[ccrobin]

Ok, I was finally able to get some actual photos.

Here is a photo of the old engine with the restrictors in place (note the retainer was already removed):



Notice how far the lifters project up (they are past the restrictor).


Now here is a photo of the new engine:


With the lifter at full height, it barely projects past the casting. It doesn't appear that the restrictor would even do anything if it were to be installed.

So am I good to bolt down the manifold and go, or do I need to remove the pushrods, install the restrictors and retainer plate, then re-install the pushrods?

Thanks for anyone who can offer assistance!

 

[Bondo]

Ayuh,...... It appears the ole motor has roller lifters, 'n the new motor has flat tappets, so no retainer necessary,....

But,... You'll have to do a "Cam Break-in" procedure when ya start it,....

 

[ccrobin]

Ayuh,...... It appears the ole motor has roller lifters, 'n the new motor has flat tappets, so no retainer necessary,....

But,... You'll have to do a "Cam Break-in" procedure when ya start it,....

Thank you Bondo! I was just reading about flat-tappets and suspected that was the case. You just confirmed for me. I will be sure to adhere to the cam break-in procedure. I have found a nice write-up on that.

Have a great weekend!