Gen2 Hemi Engine - noob here, need some information

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360duster

360duster

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Hi Guys,

i´m trying to help a guy getting a Hemi back to life. this Engine was in a 68 Charger, owner is not able to do the maintenance.....so to me it seems the engine ran several thousand street miles with a lot of valve lash (solid roller cam, some checked around 60 thousands cold now). During an oil change he found metal in the oil and stopped using the car. I found one lifter and the cam lobe damaged, the main and rod bearings look acceptable to me. It seems that no trash went trough the bearings / Cylinder walls.

So i´m a SB Guys, sucessfully built a RB Wedge before...but have no clue about the Hemi Stuff.

Are Camshafts Hemi specific or could any B/RB Cam be used? Same with the lifters, could any B/RB Lifter be used? Since the car is intended to be driven a lot, would a hydraulic roller cam be a good option in this case (low maintenance is key, no racing intended)? the owner is kinda special, i´d like to give him the least amount of things to think about, that´s why i´m thinking about the HR Cam.

Thanks for your feedback!

Michael

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Cams are Hemi specific, looks like a roller cam was already in there. Try to find out why that roller failed. Maybe oil pressure was low and oil pump a problem. There may be metal particles some where in the block. Best and surest bet is tear motor all apart and start from scratch. May be something you don't want to do, knowing how heavy and bulky hemi's are. If you have the oil may be have it analyzed. I have a hemi so I know what you're up against.
 
Hydraulic roller lifters are not a good idea and usually create tons of pushrod clearance issues among other things. As said, dig deeper to find the root cause, incorrect valve spring pressure is a common cause. I do recommend using hydraulic roller lobe cams (got a couple new ones if you need one) with solid roller lifters, tight lash and proper valve springs for street duty. Bushing lifters are another option. I’ve run this setup for a couple decades.
 
It’s unlikely the lash grew to .060 because or normal wear and tear.
I’d guess the valves were adjusted with the cam in the incorrect position, and the result was too much lash, which hammered the lifters.

The only way I can see the lash opening itself up like that is if the adjuster screws or pushrods where wearing out, or something happened and some valves got tagged/tweaked.

A leak down test could be done to rule out bent/tweaked valves.
 
thanks so far for the feedback.

Yeah, the engine will come apart for proper cleaning. And i agree with Dwayne, to me it seems that somebody did some wrong valve lashing and caused the damage. It´s a shame because there is pretty expensive stuff used at this motor.....Indy rocker setup for example.

So i should better skip the idea with the HR Cam / Lifters for a street engine?

What i learned up til now is that the cams for a Hemi are not the same than for B/RB. But what about the lifters?

Michael
 
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Or, it was just a lifter failure. Sometimes, here and elsewhere on these sites, it's like the series ' Cuban Chrome '.
 
i took it further apart...unfortunately some debris got between piston and cylinder 7 & 8....time for a complete rebuild. it´s .030" over already...hope that it´ll clean up at .040". We´ll see, will tear it down totally and then starting to make a plan.

strange thing i found: the heads are o-ringed, the wire is still there. Used with a conventional head gasket, no copper.....it seems that at least this did work.
 
360duster said:
i took it further apart...unfortunately some debris got between piston and cylinder 7 & 8....time for a complete rebuild. it´s .030" over already...hope that it´ll clean up at .040". We´ll see, will tear it down totally and then starting to make a plan.

strange thing i found: the heads are o-ringed, the wire is still there. Used with a conventional head gasket, no copper.....it seems that at least this did work.
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If you can hone the cylinders and clean them up, you can send the pistons to Line2Line coatings and they will cost them to take up the clearance.

Look them up on the web. If I’m building it I want the skirts coated.

You got lucky with the O rings. There should be an O ring in the head and a receiver groove in the block. Then you use a dead soft copper gasket. Best combustion seal there is but they don’t seal oil and coolant very well for street stuff.

Take the O rings out and either mill the heads to get rid of the groove or fill the grooves with JB Weld or similar and file it flat.
 
Line to Line coatings is in Michigan, they turn things pretty quickly. They will have questions if you use their service. I used them for my sb stroker, my bore was a little loose, good results, the piston skirt 'graphite' will break or wear itself in. Good people.
 
You need to not rush this,,,,,,how much damage to the cylinders ?
These old blocks don’t grow on trees,,,,,don’t bore unless really necessary.

Like has already been stated,,,,a really good hone,,,,at a shop even,,,,,and some coatings on the pistons can bring it all back to former glory .
Since the owner can’t do this,,,,,seems he might not have good health ?,,,,,this is not a full race engine.
Take the time to sort this out and use good judgement.
Hemi’s are not black magic,,,,,just use sound techniques,,,and they respond accordingly .

Tommy
 
yes, i´ll take my time....owner is not in a hurry because he´s got another mopar :)

It´s not a race engine, parts of it formerly were used in racing (heads, crank for example).

The owner can´t do this by himself because he´s always in fear that he´s damaging sth. due to lack of knowledge. I´m a self taught guy with some experience, just not in hemis....he trust´s me and my work, i´m considering him a friend. So the rebuild will not have the big price tag except the necessary machine work and parts bill.

I´ll consider the coating stuff, heard good things about line2line from Steve Morris.

I´ll post more pics later, thanks for your comments!

Michael
 
It's a learning curve with the Hemi. I know, I am stuck in the middle of several curves!
 
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