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73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: frotosride on December 12, 2014, 08:33:22 pm
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So I loaded the bikes (M109R & GSXR750) in the bed of the truck. For about 20 miles everything seemed fine. I was babying old blue because of the bikes. I never got over 40mph. I actually eased onto the interstate and as I approached 35 I heard what initially seemed like a loud metallic boom. My first thought was transmission, great! After the noise I couldn't get over 35. When I pressed the gas the engine would bog as if someone hooked a D5 dozer to the truck. I pulled over looked at the tranny and t-case expecting pieces to be hanging out. Pulled over again found I was a little low on tranny fluid so I filled it up and got on the road.bout a mile and it happened again. The amount of traffic was too loud but the next time it happened I knew what it was. The loudest backfire I have ever heard. I got to thinking what was the last thing engine related I touched.. Knock sensor! Ohand re-did the radiator mount. When under load I can hear valve train chatter. I use Lucas ZDDP additive and have every since the rediclouse spa took it away from us. I doubt I wiped a lobe but it's always possible. But so is a bent push rod. I left the truck on base and I'm headed to Maine with the family. Any suggestions for me to check when I get back. When I can I will try and post more when I get more time to troubleshoot. Thanks for the help.
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A bent pushrod would probably be associated with a regular misfire, even if subtle. Check engine vacuum with a gauge to rule out valve train, then check for a restricted exhaust.
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I will Check the vaccum for sure.not sure what could be restricting my exhaust because its just headers and a pipe but I will make sure something odd hasn't happened.
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So I got a chance to drive the truck an look at little under the hood. I do have a few loose to rockers but they do not seem to be lose enough to be causing my problem. I'm headed back to main so it will be after. Christmas before I will be able to check anything else. I'm still thinking its a timing issue of sorts. The truck has 168k on the original engine and nothing started until I had a heavy load in the bed.
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I unfortunately didn't get to check the oil for flakes..wish I had done that for sure but one thing I did notice is since the incident the truck had been keeping extremely smoother which barrels me. However as soon as I put it in gear I can hear the valvetrain chattering like mad. Anymore suggestioms welcomed..
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Sounds like you jumped the timing chain. BTDT.
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Sometimes
You can spot a jumped time by holding a dollar bill over the exhaust pipe
dissconnect the coil
And have someone crank it over
If it tries to suck the dollar bill into the exhaust pipe
You have a jumped timeout chain
Also it will spin over really easy and fast when you try to crank it
Sent from my iPhone using Tapatalk
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Just a suggestion, is there any possibility that a piston has gone bad. As for the rattling once it's under load or put into gear, could that possibly be the front end of the tranny. Possibly one of the bolts on the bell housing was shaken loose or the torque converter bumped wrong.
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Sounds like you jumped the timing chain. BTDT.
I think this may be the issue for sure because of the way the engine is acting. not so sure about actually skiping a few teeth but I do think that there may be a chance tha The chain has slack in it and the extra load brought it to its breaking point.
Sounds like you jumped the timing chain. BTDT.
I never thought about this but its going t be a little harde to notice with a 'y' pipe and dual out. But I may be able to try it. Either way as son as I get back I am putting the engine back tgether and limping it back to the on base hobby shop and popping the timing cover, replacing the chain and gears since they are so cheap. I do not paln on putting too much money into it because The 6.0 will be in the near futue. I just need the truck to haul the bikes to Maine.
I seriousely doubt this because this truck has been takin extremely good care of and there isn't anything that would suggest a piston faliure.
Just a suggestion, is there any possibility that a piston has gone bad. As for the rattling once it's under load or put into gear, could that possibly be the front end of the tranny. Possibly one of the bolts on the bell housing was shaken loose or the torque converter bumped wrong.
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Which base do you live on?
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I'm not currently living on base but it's where the truck is and the hobby shop is the easiest place with lifts and all kinds of tools. Either way it's Naval station Norfolk.
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(http://i1290.photobucket.com/albums/b527/frotosride1/Mobile%20Uploads/th_VID_20141227_121818_zpsni5fmsnw.jpg) (http://i1290.photobucket.com/albums/b527/frotosride1/Mobile%20Uploads/VID_20141227_121818_zpsni5fmsnw.mp4). Heres a video of blue running. No codes or my light doesn't work. And help?
I did unplug the smog pump electrically and plugged the vaccum line. Other than the other things I previously mentioned I have unplugged the IAC and no change at all. I unplugged the coolant temp sensor and idle went up slightly but all symptoms were still there.
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It sounds like an exhaust leak
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you probably blew out a spark plug insulator
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Cap.. After posting it I'm positive its an exhaust leak
Vile..I'm gonna check them in just a few. If I don't get him running in 3 days I smell intake and carb!!
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(http://i1290.photobucket.com/albums/b527/frotosride1/Mobile%20Uploads/IMG_20141227_162943_zpsvv2vs7t_edit_1419716133593_zpsi5dtxwbv.jpg) (http://s1290.photobucket.com/user/frotosride1/media/Mobile%20Uploads/IMG_20141227_162943_zpsvv2vs7t_edit_1419716133593_zpsi5dtxwbv.jpg.html)
(http://i1290.photobucket.com/albums/b527/frotosride1/Mobile%20Uploads/IMG_20141227_162802_zps5k8jjgj_edit_1419716096962_zpsjxgjaawd.jpg) (http://s1290.photobucket.com/user/frotosride1/media/Mobile%20Uploads/IMG_20141227_162802_zps5k8jjgj_edit_1419716096962_zpsjxgjaawd.jpg.html)
Looks like its been longer than I thought! Now to find a ride to get new ones..
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Pulled the rest and no obvious signs of blow by but the truck didn't run much in this condition.#'s 8, 6,4 were really easy to get out. No effort at all on initial torque to losen them. Gonna get new plugs eat and put them in tonight. Hopefully the new knock sensor and plugs fixed it
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(http://i1290.photobucket.com/albums/b527/frotosride1/Mobile%20Uploads/th_VID_20141227_214444_zpsplouova8.jpg) (http://i1290.photobucket.com/albums/b527/frotosride1/Mobile%20Uploads/VID_20141227_214444_zpsplouova8.mp4)
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OK so I figured out the hard starting issue in the previoise video. I knew it it just took me a few to remember how temperamental these TBIs are with proper voltage. Offer setting a tool bag on the petal for a while and letting the battery charge a little he started running without needing extra juice. Only died on me twice as soon as the e-fans kicked on and that's when it dawned on me bout the battery being low on juice. Right now he is ideling to get enough juice to do a test drive in the morning. I'd do it now but after the DRI king the base police are sure to stop me and I'd never do anything like that anyway...
Soooo the answer was the knock sensor. The new ones will allow the body to rotate causing mixed signals to be generated. This lead to Tue misfiring and blowing out a few insulators on the plugs ( thanks Vile )... Going to give the old boy a teat in the morning with the lighter of two bikes and pick me up a Yellow Top. These oreily batteries are good for a short time if they have any abuse or stupidity thrown at them. Thanks for the help and I will record the test drive in the morning. Off to my cosy metal tube to get some rest.
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(http://i1290.photobucket.com/albums/b527/frotosride1/Mobile%20Uploads/th_VID_20141227_121818_zpsni5fmsnw.jpg) (http://i1290.photobucket.com/albums/b527/frotosride1/Mobile%20Uploads/VID_20141227_121818_zpsni5fmsnw.mp4). No codes or my light doesn't work.
I have unplugged the IAC and no change at all. I unplugged the coolant temp sensor and idle went up slightly but all symptoms were still there.
when you first turn the key to "accessory" your CEL and battery light should be on till you start the engine
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(http://i1290.photobucket.com/albums/b527/frotosride1/Mobile%20Uploads/th_VID_20141227_215432_zpsnvplm1t6.jpg) (http://i1290.photobucket.com/albums/b527/frotosride1/Mobile%20Uploads/VID_20141227_215432_zpsnvplm1t6.mp4)
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(http://i1290.photobucket.com/albums/b527/frotosride1/Mobile%20Uploads/th_VID_20141227_121818_zpsni5fmsnw.jpg) (http://i1290.photobucket.com/albums/b527/frotosride1/Mobile%20Uploads/VID_20141227_121818_zpsni5fmsnw.mp4). No codes or my light doesn't work.
I have unplugged the IAC and no change at all. I unplugged the coolant temp sensor and idle went up slightly but all symptoms were still there.
when you first turn the key to "accessory" your CEL and battery light should be on till you start the engine
So chances are my bulb is blown. Do you know what bulb I need too buy. I just picked up new header gaskets so I will pull the cluster apart to fix that bulb today.
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(http://i1290.photobucket.com/albums/b527/frotosride1/Mobile%20Uploads/th_VID_20141228_102434_zps980yjlww.jpg) (http://i1290.photobucket.com/albums/b527/frotosride1/Mobile%20Uploads/VID_20141228_102434_zps980yjlww.mp4)
Test went good. Bought a new header gasket but when I went to replace it I managed to get quite a bit of turns on most of the bolts. Got it fixed at the block. My collector still leaks a little but I'm not that worried about it. Once again thanks for the help!
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So I drove the truck about 60-70 miles yesterday. Mostly at highway speeds of 60-75 and occasional 80 for passing. The truck ran fine except the stupid slight surging at idle when in park. Most days I just turn the truck of wait a sec then start it back up and the old man does just fine. Anyway, at the end of my trip I had slowed to 45-55 and I felt the engine stumble. Gas a little gas and bang. But he kept running. It did it again but this time he completly quit! I put the truck in neutral and coated as close to base as I could. Turned the key and he started right up. Not willing to test the limits I babied the old man to my usual parking spot. Went to an actual dealership and got an acdelco knock sensor instead of whatever brans I was getting from advanced auto. I have driven the truck about 20 miles or so since but I'm wondering if there may be something else causing this. Thankfully I didn't blow an plug insulators! Any thoughtas out there.
2 just in case I need to cover my bases so I have a carb on stand by. Its a little to big for the 350 (750 edelbrock) but it will get me to Maine and that's all I care about! My biggest question is is there anything I need to do to the factory HEI for it to function with the carb? And, what size are the supply and return line fittings on the back of the TBI so I can get an adapter?
Thanks in advance for the help!
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Sounds like it backfired through the intake. Have you replaced the ignition module?
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No not yet. It is the original one so its worth a shot. Gonna pick one up tomorrow hopefully!!
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Well you may want to do some pinpoint testing before you just throw parts at it.
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True..and I of all people know better than that. However I got a new one anyway. Replacing this has led me to a question. So I took the cap and rotor button off to replace the module and finished up then went the start it. I still had the hood up and as I turned the key I saw the rotor button sitting on the radiator. Lot of good that's gonna be. Either way I decided to check the clearance between the button and pins on the cap. There is no way that I'm not jumping a huge gap just to get to the pins on The cap. Is there a specific clearance I should have between them? Up until now I always thought that the tip of the button brushed the bottom of the pins or maybe even the inside of the pins but there is no way for that to happen inside my dist. Cap. There are wear marks on the inside of the poles but none on the tip. I'm sure gonna replace the button BC there was a little carbon on the tip and the coil end is worn down.
Comemt think of it this may be causing some of my issues like at idle.. If I'm jumping a gap between the button and cap pins it would make sense that it would stumble. On the other hand it should alos be noticeable at higher rpms!
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No the rotor does not brush the cap terminals.
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It amazes me at how little of a backfire..even just once can bust the insulators on the spark plugs. It happened with the second knock sensor incident. I didn't want to believe it at first but eventually checked and sure enough. I just got those acdelcos last week. Now I got new ones. I also replaced the coil because the pack of windings in the center were extremely loose. I have never herd this truck idle so low..its crazy. I still got a bit of a miss at idle but not sure what that could be. Either way I think I get him runninggood enough to get me to Maine!!!hopefully? Only a 650 mile trip will tell.
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Well I made it up north. Not entirely without incident.that little miss got worse at the 84/384 split but after. He king everything I could think of and replacing the distributor cap I made the old man limp the rest of the way. The miss is still there and rather bad. I pulled each plug wire from the cap to verify each was hitting....believe me its hitting good. Hit me 12 times because I'm to stubborn. I guess its possible I got a bad plug? Is their an easier way that I can test without pulling each one?
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if you have a cylinder miss you can (with the engine cold but just started) touch each exhaust port with your fingers and see which one is cooler to the touch. but the headers do heat up kind of fast so work fast
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(http://i1290.photobucket.com/albums/b527/frotosride1/th_VID_20150108_192226_zpsiexcs1nk.mp4) (http://i1290.photobucket.com/albums/b527/frotosride1/VID_20150108_192226_zpsiexcs1nk.mp4)
So you know how you work and work on something and then the very last problem presents itself. them temp drops 30* over a 2 hour period and you are worn out but gotta get it done. so after diagnosing cylinder #5 as the culprit i pulled the plug and realized the gap was way off as well as I managed to let the brand new wire touch the header and burn just enough to ground out. I regapped the plug and repaired the wire and bang it works like a champ!! thank God! now it's got a short life until 6.0 time. thanks for the hint Irish it reminded me of the water bottle technique, which as the video shows works flawlessly.
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np glad you got it figured out