Jrwhite3230 Posted November 11, 2014 Share Posted November 11, 2014 Disaster struck !! I was driving my 89 comanche and all of a sudden the loudest Boom i ever heard, and it did it four times i thought someone had fired a huge shotgunn.and i ducked! But then My truck imediatley hesitated and wouldnt stop i rolled to the side and checked everything and found that my distributer was cracked at the bolt that holds it in place. I bought a new one and replaced it. and i pulled my valve cover off to check push rods but havent yet completed this. I also found that there was no oil But no signs of leaks and it never smoked .this engine was rebuilt in 2000 ,and never smoked.I'm not sure how the oil leaked out. i also want to know if i should check my timing chain and gear? and should i pull the head and have a valve job done and replace any warped pushrod's ect... at this point what and where should i start? . the engine when i hand crank it to check compression seems extremly hard at compression stroke is this bad sign or is it just the compression suppose to be this hard to handcrnk it?? Link to comment Share on other sites More sharing options...
Keyav8r Posted November 11, 2014 Share Posted November 11, 2014 Assuming you have the plugs in, it should be hard to turn over by hand as you will be going through 3 compressions for each full revolution of the crankshaft (for a 6 cylinder, 2 if it's a 4 cylinder). The more wear you have on the rings and cylinder bores and valves/valve seats, the easier it will be to turn it over as the compression can leak by more easily. I would also turn it over with the plugs out to see if there are any hard spots. I would drop the pan first as you need to check the crank and rod bearings and the oil pump. You can also check the underside of the pistons and the cylinder bores for damage. If you find bent pushrods, you should check the timing chain and sprockets (you haven't said how many miles on the engine, but my 88 was way past due for new timing chain and sprockets at 180K). You'll also need to pull the head to check for bent valves and damage to the tops of the pistons Sounds like an excellent opportunity for an engine rebuild. Link to comment Share on other sites More sharing options...
Jeep Driver Posted November 11, 2014 Share Posted November 11, 2014 What ever happened............it doesn't sound good. Link to comment Share on other sites More sharing options...
nitroxsteve Posted November 11, 2014 Share Posted November 11, 2014 Before I pulled anything apart I would start with the basics. Put some oil in it and check the oil pressure while cranking. Then do a compression test. Was the distributor cracked or the cap cracked? If the only thing that happened is the distributor failure that would have caused your back firing. I have never heard of a distributor failing like you described so I'm not sure what could have caused it. Just don't go crazy pulling stuff apart until you have checked the basics first. You may just need a distributor and an oil change. Link to comment Share on other sites More sharing options...
hillbilly51 Posted November 11, 2014 Share Posted November 11, 2014 The way that you describe it, it sounds like a explosion inside the oil sump. The only thing that would cause that would be gasoline in the oil . I'm just speculating because I'm not saying that's what happened or that I've ever seen it. It also could have been a backfire in the muffler, so I would check the exhaust system too. If the distributor housing is truly broken and not just the cap, something went wrong in a big way. Just curious....Have you looked under the engine to see if the oil pan is still intact? Link to comment Share on other sites More sharing options...
gogmorgo Posted November 11, 2014 Share Posted November 11, 2014 I can kinda see this happening if the bearing(s?) in the dizzy failed and seized, but if that's what happened, I'd be concerned about the distributor gear and camshaft. They aren't really built for turning more than a free-spinning dizzy shaft. Link to comment Share on other sites More sharing options...
Keyav8r Posted November 13, 2014 Share Posted November 13, 2014 Edit to my previous post - first take the distributor out and look down through the hole for any evidence of damage to the camshaft gear, oil pump drive and shrapnel from the distributor gear or other parts. If no damage is found, try to turn the engine over by hand with the plugs out to check freedom of rotation. If the engine rotates freely, no catches during several rotations, then I would try putting oil in the engine, installing a known good distributor and cranking the enfpgine over several times with the coil wire disconnected to get the oil circulating. Then try to crank the engine. If it cranks and runs as it did before, drive it and keep an eye on oil pressure and oil level in the crankcase. That oil had to go somewhere - either leaked ouy through seals or burnred in the combustion chamber If it doesn't crank, check timing to make sure the timing chain hasn't jumped some sprocket teeth. This would also be a good time to pull the valve cover to observe the pushrod action as the engine turns over (look for bent or flexing pushrods. You can't know the condition of the bearings without pulling the oil pan and pump, dropping the csps one at s time snd looking at all of them. My thinking is if you pull it all the way down, go ahead and re-build it. It'll save time and money down the road, Link to comment Share on other sites More sharing options...
Jrwhite3230 Posted November 15, 2014 Author Share Posted November 15, 2014 Assuming you have the plugs in, it should be hard to turn over by hand as you will be going through 3 compressions for each full revolution of the crankshaft (for a 6 cylinder, 2 if it's a 4 cylinder). The more wear you have on the rings and cylinder bores and valves/valve seats, the easier it will be to turn it over as the compression can leak by more easily. I would also turn it over with the plugs out to see if there are any hard spots. I would drop the pan first as you need to check the crank and rod bearings and the oil pump. You can also check the underside of the pistons and the cylinder bores for damage. If you find bent pushrods, you should check the timing chain and sprockets (you haven't said how many miles on the engine, but my 88 was way past due for new timing chain and sprockets at 180K). You'll also need to pull the head to check for bent valves and damage to the tops of the pistons Sounds like an excellent opportunity for an engine rebuild. :thumbsup: :agree: i bought a new distributer and i did pull valve cover off but stopped at that point i looked for any signs of warpage without pulling anything apart but can't rely know without doing that on these engines so before i do that ill add some more oil and the new distributer .after i make sure its top dead center then ill install distributer ! see if it runs and check for any oil leaks ! then if no go ill proceed on rebuilding the top end and checking bottom end bearings /pump ect... also checking pan for any chunks of gearing or metal? . The oil displacement must have leaked out from oil plug !! because there is no way possiblefor it to leak out withou me knowing it this engine is surgicaly clean I spent 4,000 rebuilding it from bottom up. :doh: BUT maybe i shouldnt have said that because aparently somthing went amiss, I will keep you and everyone posted on it and ill follow yalls steps dilegently ,because mine has failed and I'm good at whaT i do Link to comment Share on other sites More sharing options...
Jrwhite3230 Posted November 15, 2014 Author Share Posted November 15, 2014 The way that you describe it, it sounds like a explosion inside the oil sump. The only thing that would cause that would be gasoline in the oil . I'm just speculating because I'm not saying that's what happened or that I've ever seen it. It also could have been a backfire in the muffler, so I would check the exhaust system too. If the distributor housing is truly broken and not just the cap, something went wrong in a big way. Just curious....Have you looked under the engine to see if the oil pan is still intact? yeah its still intact no leaks around gasket and no holes comming out of block no penetration in valve cover too and also i checked oil for water in it there was no oil but still i was there was no ol in the radiater eighther nor did i see any detection of water in or near the pan ill continue to investigate everything i thank you and everone here !! jrwhite3230@yahoo.com Link to comment Share on other sites More sharing options...
Jrwhite3230 Posted February 23, 2015 Author Share Posted February 23, 2015 yes oil pan intact no oil seapage but oil is gone?/ but there is no trace of oil leaks too? couldn't hav burned all that oil !! my overhead would show carbon traces if that was the case I must be overlooking something just don't know at this point ? only thing I did find was the distributor cracked at the hold down bolt ! which I know eighther way is the cause of whatever got damaged but as I pull things apart I'm sure ill find more and more damage ! Link to comment Share on other sites More sharing options...
Jrwhite3230 Posted February 23, 2015 Author Share Posted February 23, 2015 yes indeed ! I'm 54 yrs old and very experienced in so many engines cars of many types and never experienced such an explosion of this capacity everyone in a two block areah ducked out of site and even inside buildings police came from all over and it created a crowd, I had to explain to everyone best I could that it was my truck that made the explosion as I was sitting in the back seat of a sheriffs vehicle ! that's what happens when a conanche goes a stray !! everyone knows about it even news team came to investigate !! Link to comment Share on other sites More sharing options...
Jrwhite3230 Posted February 23, 2015 Author Share Posted February 23, 2015 forgive me guys I had lost my accout for a while since I posted the troubles with the atomic bomb that went kaboom in my commanche I'm back though trying to resolve it but maybe forget the whole thing and rebuild or maybe thinking crate engine or another used engine and rebuild it ?? Link to comment Share on other sites More sharing options...
BlackBeast Posted February 24, 2015 Share Posted February 24, 2015 So did you find out what was your prob? Did you pull dizzy loose and look..man that bites!!!! Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now