RDLBOX1970 Posted July 13, 2011 Share Posted July 13, 2011 OK here we go.... Stock 350 300HP with stock ignition system. Had lovely Monte towed for our first time today. Hated to see it roll on the back of a tow truck where everyone can see it. When I got home I started my troubleshooting project. 1st I checked for spark then fuel. No spark. Ok then I checked the coil. Passed ohmes test perfectly. (it's new anyways.) Checked points. (new too) 2nd I pulled spark plug #1, checked compression and test was good. Removed spark plug from cyl#8 and test was good. So that tells me the camshaft was not split between these two points! 3rd I removed the distributor to check the shaft and gears. The gear on the dist was in good shape and there was no sign of any wear or metal shavings. I tried to look down the dist hole to visually inspect the rear drive gear but could not see to well. I stuck a magnetik probe down the hole to see if I could snach any metal shavings that way and didn't bring any up. I tried to see if I could spin the rear gear with a long screwdriver and it wouldn't budge I think. Is there anything I missed to try? Other than tearing the intake off..... Quote Link to comment Share on other sites More sharing options...
KWick_70MC Posted July 13, 2011 Share Posted July 13, 2011 When you turn the car over does the distro spin ?? Did you check the condensor as well?? Double check and make sure the points are opening and closing. Should see a spark across them when turning over.. Normal everything up, Turn off all the lights in the garage and look for spark somewhere it is not suppoose to be. Hook up a spark plug directly to the coil by pulling the end out of the distro. lay it against the block and check for spark Quote Link to comment Share on other sites More sharing options...
RDLBOX1970 Posted July 13, 2011 Author Share Posted July 13, 2011 I tested for spark with s.p. wire near ground and at the coil. I checked the positive side of coil resistor wire for proper voltage then tested the coil. I removed the cap to inspect the rotor/cap and points. All in good condition and are new from tuneup early this year. I then had someone turn the engine over while I viewed the rotor and that when I knotest it not turning. Thats when I checked compression and then pulled the distributor. I am concerned that the cam broke just before the dist drive gear because I still got compression at the back of the engine as well as the front. Can my fears be true??? I couldn't hand turn the dist while still in block. It turns freely out of block without any side to side play. Quote Link to comment Share on other sites More sharing options...
KWick_70MC Posted July 13, 2011 Share Posted July 13, 2011 I would do a compression check on all the cyls... or pop the valve cover off to check rockers are moving.. if the timing chain is broke then where ever they stoped, you could be closed on both 1 and 8 cyls. Quote Link to comment Share on other sites More sharing options...
RDLBOX1970 Posted July 13, 2011 Author Share Posted July 13, 2011 That could happen. Since I might have to remove the valve cover anyways I can check this theory too. Wouldn't there be some air coming back through the carb if the cam was not moving? Quote Link to comment Share on other sites More sharing options...
KWick_70MC Posted July 13, 2011 Share Posted July 13, 2011 Maybe, maybe not.. depends on where the cam actually stopped.. I would go with timing chain before a broken cam, but cam is surely possible.. easy check and only four bolts to get the cover off.. Quote Link to comment Share on other sites More sharing options...
RDLBOX1970 Posted July 13, 2011 Author Share Posted July 13, 2011 I'll let you know soon>>> Thanks Quote Link to comment Share on other sites More sharing options...
CrazyDavey Posted July 13, 2011 Share Posted July 13, 2011 if it happens to have a nylon timing gear it may have stripped the teeth off or could be the chain, never seen a stock cam break but anything's possible...drain the oil and see if you have little nylon pieces in it... Quote Link to comment Share on other sites More sharing options...
Mo's70MCs Posted July 13, 2011 Share Posted July 13, 2011 on the nylon gear. Quote Link to comment Share on other sites More sharing options...
Mike 57 Posted July 13, 2011 Share Posted July 13, 2011 I was thinking timing gear/chain also. Quote Link to comment Share on other sites More sharing options...
wallaby Posted July 13, 2011 Share Posted July 13, 2011 It seems odd that the engine passes a compression test even though we suspect the camshaft is not turning. I suppose the cylinder could make compression if both valves happen to be closed, but then it would pull suction from the spark plug hole on the intake stroke? It has to get its air somewhere. Now here's a thought: maybe your oil pump has frozen and you sheared the pin that holds the distributor gear on the distributor shaft. You should be able to rotate the oil pump with a long screwdriver when the distributor is out...it will offer resistance, but not a lot. As for the distributor gear & shaft: when the pin that holds the gear on shears, everything LOOKS normal but the gear will spin on the shaft if it tries to pass a large amount of torque. Pretty much the oil pump holds the distributor shaft from turning and the gear spins around it...but it's hard to tell from a casual inspection because the gear is tight on the shaft and seems to be tight and pinned in place. It's not until you try to twist the gear on the shaft with tools or try to drive the gear off the shaft that you realize it has movement. The cross-pin will not want to be removed because the holes are no longer lined up. Anyway, that's about the only reason I can think that could have the camshaft turning, but not the distributor? Quote Link to comment Share on other sites More sharing options...
bobsmc Posted July 13, 2011 Share Posted July 13, 2011 funny, i saw the car yesterday afternoon driving down brookpark rd. and turned on to ridge. im local and a certified mechanic/monte carlo nut,if you need help pm me and i would be glad to stop by and help out. bob Quote Link to comment Share on other sites More sharing options...
Sam (Bones) Posted July 14, 2011 Share Posted July 14, 2011 go back to "no spark" first, no spark/no run if you determine that you have spark you haven't told us if you confirmed that it was getting fuel was there any symptoms before it quit? if you have spark, and fuel, then a complete compression test, remember to open the throttle plates some while cranking then lets see where you are at Quote Link to comment Share on other sites More sharing options...
CrazyDavey Posted July 14, 2011 Share Posted July 14, 2011 Sam, he said the rotor doesn't turn when he cranks the motor over.... Quote Link to comment Share on other sites More sharing options...
RDLBOX1970 Posted July 14, 2011 Author Share Posted July 14, 2011 Hey everyone... Thank you for your post and help. When I took of the valve cover this morning I cranked the enging while watching the lifters for movement. There was absolutly no movement! So I started to tear the front of the engine down to inspect the timing chain. Low and behold the gear was stripped and the chain was hanging on the side of the cover. I do want to say that I knew it was starting to go but hoped it would last through the summer. When I timed it at a tune-up the mark was jumping a little but ran OK. My wife was driving the car until yesterday when it failed while on the freeway (I480) when the engine just stopped running. That's where we had it towed from. Since I had it apart I dressed her up a little with some new chrome, cleaned and painted a bunch of parts and started to put it all back together with a new timing chain and gears. I just had to stop myself for the evening just about 30 min ago. Could'nt stop playing with our Monte!! Who was here one time or another? Hey Bob, Thanks for the offer. We'll get together sometime on that. Quote Link to comment Share on other sites More sharing options...
Mo's70MCs Posted July 14, 2011 Share Posted July 14, 2011 if it happens to have a nylon timing gear it may have stripped the teeth off or could be the chain, never seen a stock cam break but anything's possible...drain the oil and see if you have little nylon pieces in it... Once again master.. you have answered correctly! "I hold in my hand the last envelope. As a child of four can plainly see, these envelopes have been her'metically sealed. They've been kept in a #2 mayonnaise jar under Funk and Wagnall's porch since noon today. No one knows the contents of these envelopes, but you, in your borderline divine and mystical way, will ascertain the answers having never before seen the questions." the answer is: "here's my Rooty Tooty Fresh and Fruity waffle at IHOP" Quote Link to comment Share on other sites More sharing options...
CrazyDavey Posted July 14, 2011 Share Posted July 14, 2011 ...I was hoping I was going to get something...you buyin'??? Quote Link to comment Share on other sites More sharing options...
Sam (Bones) Posted July 14, 2011 Share Posted July 14, 2011 oops I missed the rotor not turning Quote Link to comment Share on other sites More sharing options...
wallaby Posted July 15, 2011 Share Posted July 15, 2011 Don't forget that if the gear had plastic teeth it will have pulverized them all into your oil pan. That debris has/will plug up the intake screen on your oil pump! It's not a matter of just changing your oil. There are shovelfulls of crap in there. Quote Link to comment Share on other sites More sharing options...
RDLBOX1970 Posted July 16, 2011 Author Share Posted July 16, 2011 Yea it was an aluminum gear stamped with GM on it. I changed the oil as a precaution. Quote Link to comment Share on other sites More sharing options...
wallaby Posted July 16, 2011 Share Posted July 16, 2011 Oh, that's not good news. Those plastic bits are bad. You're going to want to pull the pan and clean it out, and probably replace the oil pump pickup. Right now that pickup is probably too restricted to flow enough to keep the engine oiled. Quote Link to comment Share on other sites More sharing options...
72MC Posted July 16, 2011 Share Posted July 16, 2011 I believe this is kind-a what Mark is talking about. - Dave Quote Link to comment Share on other sites More sharing options...
RDLBOX1970 Posted July 16, 2011 Author Share Posted July 16, 2011 The old gear had no evidence of a nylon gear. I didn't get any plastic pieces from the old oil. I hope this means there were none. I want to put a new pan on but not this soon. Quote Link to comment Share on other sites More sharing options...
72MC Posted July 16, 2011 Share Posted July 16, 2011 Well the pic is actually valve seals fragments caused from to much lift on a cam but the principle Mark is describing is the same. I just wanted you to see the potential for oil starvation. - Dave Quote Link to comment Share on other sites More sharing options...
CrazyDavey Posted July 16, 2011 Share Posted July 16, 2011 The old gear had no evidence of a nylon gear. I didn't get any plastic pieces from the old oil. I hope this means there were none. I want to put a new pan on but not this soon. so where do you think all the pieces went?? Quote Link to comment Share on other sites More sharing options...
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