75k different pushrod length side to side??

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Apr 3, 2014 | 07:57 PM

edge04

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75k different pushrod length side to side??

Assembled my engine, went to start it and it is only running on 4. The drivers side is firing but nothing on the passenger. So checked fuel and spark, getting both. Check compression and none. I loosened the rocker arms and got compression, so I'm thinking pushrods are too long and leaving the valves open. Stupid me for not measuring both or all pushrod lengths.

I am running morel link bars with stock ls rockers and pedals. I came up with 7.325 pushrods.....that us 75k less than the 7.40 ones on the drivers side.

Questions:
1. Am I doing it wrong. I set to zero lash. Then I look for 1.5 turns more
2. What would cause the difference? Milled different? Valve height different?

Thanks

Apr 4, 2014 | 08:19 PM

edge04

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Anyone other than me find this odd. I measured and running 7.40 pushrods on the driver's side and 7.325 on the passenger side. I'm only able to let the car idle so no idea what this is doing for power or drivability. Anyone else with this or similiar?

Apr 4, 2014 | 08:46 PM

Darkman

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I understand the 7.40 are working on the driver's side, but did you measure the driver's side? If so, how much preload is there on the driver's side with the 7.40s?

Edit: If the lifters are Morel 5206, the preload window is from 0.030" to 0.050." It is often necessary to order custom length pushrods to accommodate the narrow window.
http://johncalliesinc.com/pdf/Adjust...licLifters.pdf

Last edited by Darkman; Apr 4, 2014 at 09:21 PM.

Apr 4, 2014 | 11:34 PM

edge04

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Thanks for the info. Yes they are. I'm still shocked that the difference between the two is 75k. I guess it could be 30-75 as that is the travel plus expansion but I am still shocked at this. I may be finding out that the 7:40 is also too long once I get the engine running at full WOT.

Apr 5, 2014 | 01:09 AM

Dyno Junkie

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Has that head or side of block been machined?

Apr 5, 2014 | 09:46 AM

edge04

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Block no. I am waiting to hear back from the machine shop. It is a very reputable engine builder on this site so hard to believe they milled them different or didn't check valve height but I can't think of anything else.