Genaro Posted March 20, 2019 Author Report Share Posted March 20, 2019 1 hour ago, datzenmike said: The left side of the block should have a vent like this... Damn....i didnt check that pipe ! Will review it tomorrow... I didnt paid enough attention to what Hainz said...."cranckcase"... Thanks a lot! 1 Quote Link to comment
datzenmike Posted March 20, 2019 Report Share Posted March 20, 2019 That pipe should have a curved hose to the PCV valve mounted on the intake under the carburetor. Make sure the valve cover hose to the air filter is OPEN or under load all the fumes (and some oil spray) will be pushed out the crankcase vent and through the PCV valve. 3 Quote Link to comment
Genaro Posted March 20, 2019 Author Report Share Posted March 20, 2019 (edited) Ok, crankcase vent pipe and PCV valve looks ok... Valve lets air flow to the manifold if i blow and closes if i suck... and vent pipe lets air flow free into the engine when i blow and comes out thru the valves cover vent... The hose between the valve cover and the air filter cover is free and "clean" ... Air also goes free blowing in reverse, from the hose to the valve cover.... Thanks! Edited March 20, 2019 by Genaro Add info 2 Quote Link to comment
Genaro Posted March 20, 2019 Author Report Share Posted March 20, 2019 On 3/18/2019 at 4:29 PM, datzenmike said: . The brace between the torsion rods can be unbolted and removed in order to remove the oil pan to get at them. If this doesn't help the bearing are already done and waiting. Im trying to remove the brace but seems like is under tension.... I have the truck on stands at the frame close to the second crossmember... Maybe i should remove the brace with the truck standing on the floor? Im doing some cleaning before removing the oil pan, already pressure washed the engine & bay... Thanks again! 2 Quote Link to comment
Crashtd420 Posted March 20, 2019 Report Share Posted March 20, 2019 Well I'm not gonna be much help but it sounds like your coming full circle back to the oil rings as the problem... it sounds like you can rule out all the external possibilities and you said you did the valve seals.... I dont know if theres a way to check them without removing a piston..... Maybe borrow a bore scope to look at the cylinder walls through the spark plug hole.... By the way truck sounds pretty good.... 3 Quote Link to comment
Crashtd420 Posted March 20, 2019 Report Share Posted March 20, 2019 I keep forgetting this is a 720 because of the L18, keeps messing with my thoughts.... If it's a removable crossmember like the 521/620 they are under some tension.... If you can get all the bolts out just use a pry bar to free it.... Probably will need some persuasion to get things back in also... I believe that's normal, and also why its there.... 3 Quote Link to comment
Genaro Posted March 20, 2019 Author Report Share Posted March 20, 2019 34 minutes ago, Crashtd420 said: I keep forgetting this is a 720 because of the L18, keeps messing with my thoughts.... If it's a removable crossmember like the 521/620 they are under some tension.... If you can get all the bolts out just use a pry bar to free it.... Probably will need some persuasion to get things back in also... I believe that's normal, and also why its there.... Thanks! I was able to remove it like you said, with some persuasion... I also removed the oil pan bolts but it doesnt come out , looks like i will have to remove the steering bar that joins one wheel with the other.... And yeah, i also like how it sounds... But pretty sure that neighbours dont...! 😀😀 2 Quote Link to comment
Crashtd420 Posted March 20, 2019 Report Share Posted March 20, 2019 Looks to me like you do.... maybe you could just unbolt the pitman arm from the frame and it would hang enough to get the oil pan out..... 2 Quote Link to comment
Genaro Posted March 20, 2019 Author Report Share Posted March 20, 2019 1 hour ago, Crashtd420 said: Looks to me like you do.... maybe you could just unbolt the pitman arm from the frame and it would hang enough to get the oil pan out..... Indeed, i was able to remove the pan by unbolting the auxiliary swiveling thing and moving the whole steering system to the front... Thanks! 3 Quote Link to comment
Genaro Posted March 21, 2019 Author Report Share Posted March 21, 2019 Admision valves from 4 to 1 2 Quote Link to comment
Crashtd420 Posted March 21, 2019 Report Share Posted March 21, 2019 It would be nice if the smoke is just that shit burning off..... Isnt there a water trick or solution that could clean that some, without removing the head.... I've heard of using a spray bottle and misting water into the intake or something along those line..... Please don't just do it because I said it... look up if it's TRUE or not or maybe someone else can say for sure.... 2 Quote Link to comment
datzenmike Posted March 21, 2019 Report Share Posted March 21, 2019 Unbolt the idler arm and the steering should drop down enough. The idler arm is on the right side and is the opposite of the steering pitman arm. There is a lot of oil in the intake ports, a LOT, and on the valves. It can only get there from the valve guide seals or the PCV valve but not the rings. Again, maybe the old bearings are throwing too much oil around and it's blowing out the block vent. 2 Quote Link to comment
Genaro Posted March 21, 2019 Author Report Share Posted March 21, 2019 (edited) Exhaust ports from 4 to 1 3 hours ago, datzenmike said: There is a lot of oil in the intake ports, a LOT, and on the valves. It can only get there from the valve guide seals or the PCV valve but not the rings. Again, maybe the old bearings are throwing too much oil around and it's blowing out the block vent. Yes, oil starts to show only at the head part of the admision... Valve seals not tight enough? The new ones that i installed fitted ok....Valve guides worn? Even tough there is some oil traces in the PCV inlet to the manifold, the rest of the conducts are pretty clean...i dont think that the oil camed from the PCV, but i dont know a lot about mechanics, thats why i ask so much....😀😀 Thanks! Edited March 21, 2019 by Genaro 2 Quote Link to comment
datzenmike Posted March 21, 2019 Report Share Posted March 21, 2019 The gas spray from the carburetor will wash it away and transport it down to the valves. The exhaust ports are heavily coated from the the oil burning, and that's to be expected. You said the seals were replaced and the valves did not wiggle. They probably wouldn't wiggle if they were closed and on their seats. Usually the valve will be lifted to normally open height and checked for 'wiggle'. Hard to do with the head on. 3 Quote Link to comment
Genaro Posted March 21, 2019 Author Report Share Posted March 21, 2019 (edited) 14 minutes ago, datzenmike said: The gas spray from the carburetor will wash it away and transport it down to the valves. The exhaust ports are heavily coated from the the oil burning, and that's to be expected. You said the seals were replaced and the valves did not wiggle. They probably wouldn't wiggle if they were closed and on their seats. Usually the valve will be lifted to normally open height and checked for 'wiggle'. Hard to do with the head on. Yes, makes sense what you say about the oil/fumes that could be washed down... Seals were replaced by me as the first try to stop the oil intrusion into the cylinders... the old ones looked and felt like bakelite or plastic and were severely worn... I've used the rope method, so i was able to push the valves open against the rope and wiggle them...i didnt found any noticeable movement...nor rough sliding when turning the valves against the seats with my fingers... 🤔🤔🤔 Edited March 21, 2019 by Genaro 2 Quote Link to comment
datzenmike Posted March 21, 2019 Report Share Posted March 21, 2019 Rope is the best way. 2 Quote Link to comment
Genaro Posted March 21, 2019 Author Report Share Posted March 21, 2019 Intake cyl 1 😱😱😱 2 Quote Link to comment
Genaro Posted March 21, 2019 Author Report Share Posted March 21, 2019 Lower part of cylinder 4 On some of them there are some tiny scratches at the bottom part of the cylinder, below the line of the rings and to the sides of the cylinders....left and right, where the pistons have those parts that extend down... Damn, is hard to find the correct words in a second language...😀 1 Quote Link to comment
Genaro Posted March 21, 2019 Author Report Share Posted March 21, 2019 Some weird gunk was at the bottom of the oil pan...mixed with pieces of solidified rubber from the gasket... Gum is gray color, maybe they added some type of additive? Or could be the 30+ years being there and becoming a new petrochemical substance...😀 3 Quote Link to comment
Genaro Posted March 21, 2019 Author Report Share Posted March 21, 2019 Cylinder 4 , looks perfect... Also the rod bearings and the rings...tough like Mike said, its full with oil in the little cells 3 Quote Link to comment
Genaro Posted March 22, 2019 Author Report Share Posted March 22, 2019 Valve guides are shot... Now that i removed the head i was able to wiggle them from the dish part and all of them move a lot... and on top of the discs there is a lot of cooked oil deposits... Im sending it to a machining shop this afternoon and will buy the crank and rods bearings in standard size to change them... Should i change the rings? Cylinders look free of marks/burrs and what worries me is that the parts that are for sale here are from unknown origin...but probably chinese or taiwanese... Quote Link to comment
Crashtd420 Posted March 22, 2019 Report Share Posted March 22, 2019 2 hours ago, Genaro said: Valve guides are shot... Now that i removed the head i was able to wiggle them from the dish part and all of them move a lot... and on top of the discs there is a lot of cooked oil deposits... Im sending it to a machining shop this afternoon and will buy the crank and rods bearings in standard size to change them... Should i change the rings? Cylinders look free of marks/burrs and what worries me is that the parts that are for sale here are from unknown origin...but probably chinese or taiwanese... You should probably remove the bearings first, and make sure the crank was never ground..... Maybe just checking the rod bearings will be enough to tell you.... There should even be size markings on them.. And if it was me I would probably change the rings.... your in this deep now, I dont think rings are too expensive... And same thing with those you need to double check the motor hasn't been bored oversize..... Also replacement may not be necessary.... the bearing should be obvious if bad and if in good shape then they can just be used.... But buy the sounds of it the head is hopefully the issue.... the rest would just be added insurance and piece of mind... 2 Quote Link to comment
Genaro Posted March 22, 2019 Author Report Share Posted March 22, 2019 (edited) 17 minutes ago, Crashtd420 said: You should probably remove the bearings first, and make sure the crank was never ground..... Maybe just checking the rod bearings will be enough to tell you.... There should even be size markings on them.. And if it was me I would probably change the rings.... your in this deep now, I dont think rings are too expensive... And same thing with those you need to double check the motor hasn't been bored oversize..... Also replacement may not be necessary.... the bearing should be obvious if bad and if in good shape then they can just be used.... But buy the sounds of it the head is hopefully the issue.... the rest would just be added insurance and piece of mind... Yes , i've ordered the rings too... Crank hasnt been machined... bearings have "standard" stamped on them . Cylinders and rings are also the original ones...looks like is the first time that this engine is opened... Thanks for the suggestions! Edited March 22, 2019 by Genaro Add photo 2 Quote Link to comment
Crashtd420 Posted March 22, 2019 Report Share Posted March 22, 2019 (edited) Way to get after it...... Bearing actually looks good, but new ones wont hurt...... Watch where those holes go it does matter...... Edited March 22, 2019 by Crashtd420 2 Quote Link to comment
datzenmike Posted March 22, 2019 Report Share Posted March 22, 2019 I think the top shells have a lengthwise oil groove, the bottoms do not. Cranks only get turned if the bearing spins. Usually they are always good. That's why the bearings are there, to take the wear and be replaced easily. You can gently tap the top main bearing shell and get it to rotate around the crankshaft enough to remove without taking the crankshaft out. Oil the new one and replace in reverse. I just did this late last fall. 2 Quote Link to comment
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