Help! 360 with 302 heads no compression

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And from that pix, they are about 'half a ball' different in length, which is what the listed variation is in the early vs. late ones for '92: 0.15-0.16" difference.

I ordered the shorter ones off rockauto. Autozone doesnt even give me an option for the shorter ones. O'Reilly has to order them from 5 different locations and charge me shipping for each.
 
You're trying a reasonable alternative, based on the PN's and listings. It may well get you out of the woods but there is still a possibility that the valves are bent; the .15" long pushrods were opening the valves an extra .225" or thereabouts, and that is a lot of extra lift.

Or something else may pop up in the overall length setup. So just be aware.
It's more about past services on the head, gasket thickness, valves stem height increases with valve jobs and not all will cut the stem height back to factory tolerance.


Heads milled
Valves faced/ground
Seats ground
Gasket maybe thinner

All that equates to... is the necessity of a shorter push rod.
As above, there are variables that are unknown (to us). What head gaskets did you use? Out of a standard Felpro kit?
 
Yeah i got a standard felpro kit. The pistons are the original dish pistons. I will see tomorrow when the push rods come in
 
OK, the standard Felpro's in the kits (you probably got 8553PT's) are thicker than stock so that would have helped a bit. I guess you're gonna find out!
 
Look at the top of your rocker arms. The roller cam motor rockers don't have oil holes in the pushrod sockets, the sockets oiled through the pushrod.
 
Look at the top of your rocker arms. The roller cam motor rockers don't have oil holes in the pushrod sockets, the sockets oiled through the pushrod.
I used the rocker arms from the 308 heads that were cracked. They were the same as the 302 ones. But i used them cause they were fine
 
Well, You'd better give the valve seals a real careful inspection before continuing, I don't know how close that clearance was but it bears a good lookie-see.

Im going inspect them and do a leak down test on each cylinder after i put the new push rods in. before i go any further. But when i first had it together i rotated it by hand and didnt get any binding
 
Look at the top of your rocker arms. The roller cam motor rockers don't have oil holes in the pushrod sockets, the sockets oiled through the pushrod.

Interesting tidbit there.

So, the “correct” pushrods would have oil holes.

Edit: I looked up the pushrods....... 6.777oal, with oil holes.
This book shows them used from 89-92.

88 318 w/hyd roller shows 6.802 w/o oil hole.
 
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Edit: I looked up the pushrods....... 6.777oal, with oil holes.
This book shows them used from 89-92.
Interesting.. whose book? Melling shows MPR-381 with a length of 6.707". Measured differently? No ready info on whether it has the holes....
 
SBI

The SBI length might be OAL, and the Melling might be “gauge length”.

The difference in the SBI book between the 88 length of 6.802 and the 89-92 length of 6.777 could easily be the addition of the holes in 89, if you’re measuring the actual OAL.
 
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Thats interesting. I didnt know that. Well i got the new push rods in. I got the drivers side done and started on the passengers side. With all my damn luck i pulled out the new pushrods and one was wrong. Someone must of put it in during the packaging from rockauto. I just went to a local dealer and got one. I adjusted the timing and did a compression test and got around 120 on all cylinders. Truck fired up fine. I just need to drive it around and work out the bugs. Thanks everyone for the help
 
Oh yeah heres a pic of the wrong pushrod

20190308_140507.jpg
 
Thats interesting. I didnt know that. Well i got the new push rods in. I got the drivers side done and started on the passengers side. With all my damn luck i pulled out the new pushrods and one was wrong. Someone must of put it in during the packaging from rockauto. I just went to a local dealer and got one. I adjusted the timing and did a compression test and got around 120 on all cylinders. Truck fired up fine. I just need to drive it around and work out the bugs. Thanks everyone for the help
would love to hear how this motor runs out when you get it all sorted out!!
 
Yeah that one is a tad long LOL. Glad you got it going and the the compressions are all good and even.
 
Just a tiny bit too long so you never noticed packing them up... great customer service at rockauto.
Rockauto sucks! Most of my orders from them have been screwed up. High shipping charges, crappy returns. I ordered a "matched" set of A/C belts for my Ramcharger last month and they sent me 2 different brands of belts that were so far off from being a matched set. Would have cost me more to ship them back, than what it was worth.
Ill just order from advance auto from now on and use the 30% discount code with free shipping and returns.
 
Its a sweet truck i picked up for 300 bucks. 92 d250, 3/4 ton. Needs a ac compressor but its all there, interior is really nice, body is really nice. Jas a goose neck hitch in the back and a regular hitch, and trailer brake. Push bar in the front, front visor and running bars. Also has a deep tranny pan. The guy was going to scrap it cause he couldnt get it running right.
 
Its a sweet truck i picked up for 300 bucks. 92 d250, 3/4 ton. Needs a ac compressor but its all there, interior is really nice, body is really nice. Jas a goose neck hitch in the back and a regular hitch, and trailer brake. Push bar in the front, front visor and running bars. Also has a deep tranny pan. The guy was going to scrap it cause he couldnt get it running right.
Cool , BUT fact still remains: Why were 6+ original pushrods bent when you pulled the manifold & 2/ why were there valve marks on the dished piston tops, when you pulled the cracked heads ?? (Unless I read wrong earlier) Did someone prior miss a shift big time ?? - valves kissing pistons .
3/ As for that obviously too long pushrod ex Rickautos; that was no mistake...their Comeback/return service is NON EXISTANT (Speaking from experience) any comebacks & they treat their customers with scorn & arrogance, I only really buy their wholesale closeouts and/or limit to something absolutely needed or known quotiant blister type packed & then with a "suck it & see (what turns up) mindset.
Just a fair warning to others on less well trodden path in their direction.
4/ The amount of Varnish on the inside of that 360 I'd soak all bores in diesel & run a few cans of STP injector cleaner/top end lube/Solvent for a few gastank fulls, be surprised how much more it'd free up.
Still be suspicious of that slack in timing chain still: it'll RETARD your Cam timing too, so I'd run an offset Crank key 4° or Drill the back side of the Camgear for an offset button if it doesn't use a keyway Cam snout ( not familiar with Roller Cams).
Good outcome anyways, sounds like a find, your Truck & ya know, sometimes the cheapest buys turn out to be most satisfying etc.
Cheers Trev.

Screenshot_2019-03-10-06-11-12.png
 
I dont have pics of the original heads but the valves were full of gunk like bad gas. They needed to be hammered out. After cleaning the heads I found the cracks. I cleaned tank.
 
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