Well, it's my turn to ask for suggestions..

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Yeah a bum Tc wil show up right off the line as a lazy pig of a pos motor. But it doesn't contribute to break-up.
Per #27 " I have discovered that if you floor it, as the rpm's build it starts to cut out. "
That sounds like valve float.(or Point bounce Heehee)
 
318willrun said:
Next is the timing chain. What are the suspicions of a faulty chain????? I put a Mellings double roller in it that offers the advance/retard timing of 4* or straight up. I used the straight up.
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I'd time the cam next unless you want to check the exhaust. Do you have access to a dial indicator? Follow standard procedures. If no dial indicator, use a dial caliper and check the intake and exhaust valve retainer heights at overlap on #1, and find where they are exactly equal while turning in the CW direction. See if the crank timing mark is very near to the TDC mark. If off by around 15 degrees or more, you are off a tooth.

BTW, new valve springs or stock ones or what?

BTW, A/J refers to glasspacks; is that what you have? They are somewhat notorious for losing the pack if the innards rust out, and the packing often moves into the tailpipe and blocks it up. If they are near the tips, shove a broom handle up each pipe to see it moves freely through the glasspack. Otherwise, use a sewer rooter. (Don't try this with standard mufflers.... obviously)
 
good stuff being posted...
-As far as the torque converter, it is the factory one the 318 used, and the 318 would turn the tires.
-As far as the exhaust, would glass packs turned backwards really cause this? I have no tailpipes, it ends in glass packs before the rear end. I installed it as a temporarily thing.
-I just have to take the balancer off and timing cover and I'll check the timing marks.
-I believe the springs are new with the new long block (it has remanufactured heads, i'm sure)
I truly believe, now more than ever, between the chain/cam I have terrible valve timing.
 
Ima sticking to exhaust or springs, or both. With no tailpipes, checking the exhaust is easy. The louvers in the Gpacz , need to be facing in the correct direction. The muffler are usually marked in and out. But the louvers by themselves may not be to blame, if the muffs are correctly sized.
We used to put one size bigger ones on backwards on purpose. They were a bit louder, but with the louvers pointing backwards we were fast. Or so we thought... Heehee.
Naw, the big thing with Gpax was they tended to puke their packing. I think the ones with holes instead of louvers were better at keeping their packing,packed; but they were noisier too. Shine a lite in them;easy check, or drop them and let her rip!
BTW, I don't suppose you stuffed the headpipes into the glasspacks, and muffler clamped them too close to the ends, crushing the headspipes. Naw, I didn't think so.
 
AJ/FormS said:
Ima sticking to exhaust or springs, or both. With no tailpipes, checking the exhaust is easy. The louvers in the Gpacz , need to be facing in the correct direction. The muffler are usually marked in and out. But the louvers by themselves may not be to blame, if the muffs are correctly sized. We used to put one size bigger ones on backwards on purpose. They were a bit louder, but with the louvers pointing backwards we were fast. Or so we thought... Heehee.
Naw, the big thing with Gpax was they tended to puke their packing. I think the ones with holes instead of louvers were better at keeping their packing,packed; but they were noisier too. Shine a lite in them;easy check, or drop them and let her rip!
BTW, I don't suppose you stuffed the headpipes into the glasspacks, and muffler clamped them too close to the ends, crushing the headspipes. Naw, I didn't think so.
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Alright, they are now on my checklist... I cut the Y-pipe and used those as headpipes. I ran flex exhaust pipe for about 18 inches then clamped my glasspacks to them. So, if I stick a rod longer than the glass pack through there, it's OK? They had a 2 inch open hole all the way through them when I installed them, could look right through them....
I
 
Well, that would kinda depend on the size of the "rod",lol. A broomstick was mentioned. Ima thinkin the "rod" should be a minimum of 1.5 inches diameter, and I would like it to pass through the flex pipe all the way into the headpipes. I'm thinking a small plastic vacuum cleaner hose might do it, like on a "shopvac"
Hey if you are still running the factory manifolds you might want to prove the heat-riser valve is open. I know you said the previous engine ran fine, but it just takes a sec to check.
BTW, in my experience,an engine with valve float/lifter pump-up runs normal, right up to, when the valves fail to close. Then it flutters a bit, and goes flat, and more or less refuses to rev any higher.Then when you back out of it,because it takes time for the lifters to bleed back down, and they don't all bleed down at the same time, the engine runs quite rough,cuz the valves are not all closig properly. If you allow the Rs to come down too far, it may stall. It may not restart without a great deal of trouble or time, and will continue to run rough until the lifters are back to normal.This assumes the valve stems did not get bent during the event.
A plugged exhaust is a more gentle event, and the engine never runs rough after backing out of it. It just seems to reach a point when it doesn't want to rev any higher, and this point varies with load.It might rev progressively lower in each gear range.
-I should also mention, that a long long time ago, when I was really broke, I intentionally ran a teener with the cam advanced one tooth. The chain was so stretched, that performance was dropping. Nothing like yours, but I could feel it wasn't right, and the quick check revealed a well worn chain.I had previously installed a used 340 chain kit on her as I do on all my teeners. No, not all used; but,all roller chains.lol. So I simply moved the chain over one tooth, slapped it all together and reset the ignition timing. Voila, I was back in action.Did I mention I was broke? What I learned from that, was that there is a lot of leeway in cam timing on a small-cam engine.If I remember, the stock teener cam is under 200*@050. I seem to remember it being 192ish. That's a small cam.But it had to be, to keep the Dcr up, with that pitiful compression ratio.
 
318willrun said:
170 psi says it has plenty of compression to run. For instance, 3 cylinders showing 50 psi would indicate a problem. The engine came with remanufactured heads, I'm sure, which included new valve springs. Not high performance valve springs, just new replacement springs is how parts store motors would most likely build it. I'm really doubtful valve springs are the issue here. Again, I've shared about all the info I have on the motor. I did not buy it new, it was from craigslist. I just took enough of it apart to verify it was new.
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It has plenty of compression, yes. But what's in the cylinder? You need compression, spark, and fuel (air fuel mix). If the cylinder is partially still full of exhaust, or the incoming air is facing hardships just to enter the cylinder, you can have all the pressure you want and it will still run like ****. I've taken several of these engines apart. Mass rebuilder stuff is out and out the worst. They do not remanufacture. They repair used parts, and modify the worn crap to work with it. Like using guide liners that are thicker, and turning the valve stems smaller because replacing guides and valves ads to the rebuilding cost. I've also seen valves that were turned down until they were .100" smaller in head diameter because that's what it needed to get a seat angle cut on it. It's not a big deal if the valves are sunk - it will still run and have good cylinder pressure and you can whack off the ends of the stems to keep them sort of even. Of course you ground through the surface hardening of the stem but it only has to go through the 12 month warranty. The springs are not normally replaced. Instead they have thick shims under them to bring them back into tolerance even though they are whipped. Those you can see with the valve cover off. It's my opinion that you did not take it apart far enough, or you missed some things. It's running - which means it's passed the quality control of the rebuilder who only cares that it runs for the least a mount of investment on his part. The peformance is telling you there is a problem or a series of them. I hope it's something stupid like a rats nest or whatever. It's not the cam although that cam on factory springs won't work well either.
 
is the motor broken in yet. usually it takes from about 100 to 500 miles sometimes depending on how the engine was built. sounds like it was built tight with that kind of compression. just throwing ideas out. my 318 was a slug until it had about 350 miles on it. I mean a real slug.
 
Some more good stuff. AJ/forms, I like the "advancing one tooth" on the worn chains. lol. Yes, it's a 360. Moper, you raise a lot of doubts in my mind about the engine. I have 318 magnum and the RPM intake, along with a roller cam with fuel pump eccentric from an 89 360, and the rest of the stuff that would be needed. Hmmm..... omhamoparguy, no, the motor is not broken in yet, but of the motors I've rebuilt, never have I experienced anything like this.
 
Glass packs on backwards -- LMAO!!! AJ NOW THATS FUNNY ! thats why he's a Gooooollddd member...
 
tarvin890 said:
sounds like something "plugged up"... weather it be in the intake system or exhaust to me
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once again...


you have verified fuel, spark and timing....leaves little else... although the converter idea might grow on me but i think you would feel that in its own way,

leave a rag in the intake or port somewhere?
 
Dumb questions and ideas:
- Do you have good oil pressure?
- Have you put a wrench on the snout bolt of the crank and see if you can turn it fairly easily with the plugs out?
 
Rags in the intake are possible, however, I painted the intake hemi orange and it sat in my house for a couple of week. When I installed it, I specifically examined the all the ports to be sure no "crud" made it into the cylinders. I'm having a hard time with the exhaust being plugged, because I wire-wheeled the manifolds, cleaned them, removed the heat flap, totally examined the Y-pipe pieces that I cut to use as down pipes, used new 18 inch flex pipes that connected to almost new glasspacks that I held up and was like looking through a straight pipe.
I do have oil pressure, but I just have the dummy light. It goes off immediately. I have plenty of oil on the rockers and gets there immediately.
I'm truly thinking it's a faulty cam/chain or something with the valve timing. I have air, fuel, great cylinder pressure, good ignition timing, and most other components that worked great with the 318, leaving me with basically only valve timing left. I must go here next...... If I can't find it in the valve timing (I will try a different cam/chain if needed), I'm thinking I will have to pull the motor and totally disassemble it to find what is going on. If this is the case, I'll probably throw the 318 mag in there because I have limited time, and winter is moving in around the corner.
 
Folks are just throwing ideas out there. The plugged exhaust suggestions are just because it will cause your symptoms.

One more: If it is a settable advance/retard cam set, sometimes the slot to use is not obvious. But if it is as dead as you seem to report, then it is more likley a tooth off, or more.
 
it seems to me that you have checked all the obvious things out. I would suspect the torque converter is mal functioning. or miss application. i have an toggle switched electric lock up in my 904 and if i leave the torque converter locked up at idle ,its noticeably lame until i remember to switch it back. no way that 170# in all cylinders could be cam, compression, timing etc. Has to be external. Collapsed exhaust?
 
golden boy said:
it seems to me that you have checked all the obvious things out. I would suspect the torque converter is mal functioning. or miss application. i have an toggle switched electric lock up in my 904 and if i leave the torque converter locked up at idle ,its noticeably lame until i remember to switch it back. no way that 170# in all cylinders could be cam, compression, timing etc. Has to be external. Collapsed exhaust?
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Thanks for the thoughts. Again, the TC was behind my 318 6 weeks ago, and worked just fine. I could get rubber with 235/60 R 15's and traction bars with my 318 2bbl and single exhaust...lol. First time I bought an engine instead of building one, and I think this may be my last.... lol. I'm not sure right now if I could spin a tire on loose gravel. Tomorrow I will inspect the timing chain. Couldn't get to it today.
 
golden boy said:
no way that 170# in all cylinders could be cam, compression, timing etc. Has to be external. Collapsed exhaust?
Click to expand...
My thought is that if the cam is advanced a tooth or more, even if the cylinder filling is not optimum, you will get plenty of compression pressure: the slow cranking speed would still allow decent cylinder filling and overlap is moved ahead of the start of the intake stroke of the piston so you don't get as much pulled back in via the exhaust, and it will compress well as the intake is closing so much earlier on the compression stroke. The high compression readings may actually be a sign of advanced cam timing. But, I have never run any tests on this, and so that is just a guess.
 
nm9
I have run the tests and your thinking is spot on. I was trying to lose some pressure, by closing the intake a little later. Gains are small over 4 or 5 degrees, but measureable. And yes, it worked.
 
nm9stheham said:
My thought is that if the cam is advanced a tooth or more, even if the cylinder filling is not optimum, you will get plenty of compression pressure: the slow cranking speed would still allow decent cylinder filling and overlap is moved ahead of the start of the intake stroke of the piston so you don't get as much pulled back in via the exhaust, and it will compress well as the intake is closing so much earlier on the compression stroke. The high compression readings may actually be a sign of advanced cam timing. But, I have never run any tests on this, and so that is just a guess.
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Some good stuff right here... this thought on the high cylinder pressure due to cam being too far advanced is thinking... I never thought of that.
 
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