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Author Topic: Valve interference?  (Read 2427 times)

December 28, 2018, 04:40:00 pm

Hobbs

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Valve interference?
« on: December 28, 2018, 04:40:00 pm »
I'm installing a freshly refurbished head in a 1981 pickup. I have the crank timing mark at tdc and the cam at tdc so I can slide in a cam lock tool and the injection pump so I can slide in the locking pin. When I rotate it counterclockwise to set the injection timing I rotate the crankshaft less than a 1/4 turn and it meets resistance and it doesn't feel like compression, it feels like a metal on metal  interference. I moved everything back to tdc double checked tdc and tried again  with the same result. I tried turning it clockwise and same the same thing happened.
This truck has been cobbled together and i cant tell what parts are involved and if they are the right ones... if I remember correctly the flywheel and pressure plate have a bolt pattern that can only be put together one way? If true is there a chance I have a fly wheel that is off?



Reply #1December 29, 2018, 11:10:08 am

libbydiesel

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Re: Valve interference?
« Reply #1 on: December 29, 2018, 11:10:08 am »
If someone did not pay attention to the flywheel/pressure plate alignment pins it can be installed more than one way. 

Reply #2December 29, 2018, 12:33:22 pm

Hobbs

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Re: Valve interference?
« Reply #2 on: December 29, 2018, 12:33:22 pm »
Well the flywheel is definitely off. Any tips for finding tdc using a dial indicator?

Reply #3December 29, 2018, 01:47:44 pm

libbydiesel

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Re: Valve interference?
« Reply #3 on: December 29, 2018, 01:47:44 pm »
You can use a dial indicator through the injector hole and through the pre-chamber insert to measure on the piston crown.  Another method I like is to use a clear hose that fits tightly in the glow plug hole.  Use #4 as its TDC is the same as #1 but it is easier to access.  Seal around the hose with a bit of grease.  Put the other end of the hose in water.  Turn the crank one direction.  Note whether bubbles come out or water goes into the tube.  If water is being drawn in, then rotate the crank the other direction.  Go very slowly and watch for the moment the air stops being pushed out and instead begins being drawn into the tube.  That precise moment the crank is at TDC for #1 and #4.

Reply #4December 29, 2018, 01:49:37 pm

Hobbs

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Re: Valve interference?
« Reply #4 on: December 29, 2018, 01:49:37 pm »
Thanks! I confirmed it but ways.  You're the man!

Reply #5January 01, 2019, 01:39:19 pm

smutts

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Re: Valve interference?
« Reply #5 on: January 01, 2019, 01:39:19 pm »
Quote
Another method I like is to use a clear hose that fits tightly in the glow plug hole.  Use #4 as its TDC is the same as #1 but it is easier to access.  Seal around the hose with a bit of grease.  Put the other end of the hose in water.  Turn the crank one direction.  Note whether bubbles come out or water goes into the tube.  If water is being drawn in, then rotate the crank the other direction.  Go very slowly and watch for the moment the air stops being pushed out and instead begins being drawn into the tube.  That precise moment the crank is at TDC for #1 and #4.

Elegant, and cunning, Libbydiesel, that is a nice one! ;D

Don't have a brain fart and suck the water into the engine though :'(
« Last Edit: January 01, 2019, 01:50:38 pm by smutts »

Reply #6January 25, 2019, 03:00:54 am

timpaines

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Re: Valve interference?
« Reply #6 on: January 25, 2019, 03:00:54 am »
This is the issue with me and now i am happy to find the answer of this.
 rotate it counterclockwise to set the injection timing I rotate the crankshaft less than a 1/4 turn, there is no interference now..
« Last Edit: January 25, 2019, 03:03:17 am by timpaines »
newbielink:https://epsonsupports.net/blog/how-to-fix-printer-offline/ [nonactive]

Reply #7January 26, 2019, 12:07:31 am

fatmobile

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Re: Valve interference?
« Reply #7 on: January 26, 2019, 12:07:31 am »
 Put the right mark on the crank when you found it right?
 The clutch might be put on wrong,.. or it might be a gasser clutch.
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