85lebaront2 Posted May 7, 2023 Author Share Posted May 7, 2023 Good job! That makes sense and looks good! Thank you sir! I stopped by the Chrysler, Dodge, Jeep, Ram dealer in Salisbury and ordered a 6100997 dowel pin that is used in the end of the cams to align the gears to them, $4.00. I picked it up in April when I went back up. I drilled through the spacer washer and a short distance into the slot on the 2.5L gear then drove the pin in so it locks the two gears in alignment. In disassembling the short block, I found some interesting things, on the rear pan rail there is a letter stamped in line with the connecting rod big end, this one had D,C,C,C front to rear and after a preliminary cleaning of the pistons found the same letters there. I posed the question of their meaning to Dave Zatz on AllPar, and he asked some older Chrysler workers. They are what I suspected, piston and bore size grades for a closer fit. He took my pictures and in a section called MoTales, he did a write up on it. https://www.motales.com/engines/misc/piston-matching.php Now I am trying to decipher the exact size (they are oversize) the Venolia forged 2.5L Hybrid pistons are so I can order rings for them and have the block bored. They are at least 0.50 mm over and may even be 0.75 mm over. Problem is Venolia is out of business and information is very hard to find. Link to comment Share on other sites More sharing options...
Gary Lewis Posted May 7, 2023 Share Posted May 7, 2023 Thank you sir! I stopped by the Chrysler, Dodge, Jeep, Ram dealer in Salisbury and ordered a 6100997 dowel pin that is used in the end of the cams to align the gears to them, $4.00. I picked it up in April when I went back up. I drilled through the spacer washer and a short distance into the slot on the 2.5L gear then drove the pin in so it locks the two gears in alignment. In disassembling the short block, I found some interesting things, on the rear pan rail there is a letter stamped in line with the connecting rod big end, this one had D,C,C,C front to rear and after a preliminary cleaning of the pistons found the same letters there. I posed the question of their meaning to Dave Zatz on AllPar, and he asked some older Chrysler workers. They are what I suspected, piston and bore size grades for a closer fit. He took my pictures and in a section called MoTales, he did a write up on it. https://www.motales.com/engines/misc/piston-matching.php Now I am trying to decipher the exact size (they are oversize) the Venolia forged 2.5L Hybrid pistons are so I can order rings for them and have the block bored. They are at least 0.50 mm over and may even be 0.75 mm over. Problem is Venolia is out of business and information is very hard to find. Really interesting, Bill! Hope you can find the pistons you need. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted May 7, 2023 Share Posted May 7, 2023 Really interesting, Bill! Hope you can find the pistons you need. I think Bill has the pistons and just needs to know how to bore the block and which rings to use. Closer every day! Progress is GOOD! Link to comment Share on other sites More sharing options...
Gary Lewis Posted May 8, 2023 Share Posted May 8, 2023 I think Bill has the pistons and just needs to know how to bore the block and which rings to use. Closer every day! Progress is GOOD! Yes! I misunderstood. He does have the pistons and is just trying to find out what size they are. And yes, progress is good! Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted May 8, 2023 Share Posted May 8, 2023 Yes! I misunderstood. He does have the pistons and is just trying to find out what size they are. And yes, progress is good! I'm sure Bill can mic the pistons but he can't know the alloy or how much they will expand at operating temperature. Venolia would have produced these for a specific bore (within a couple of tenths) Pistons aren't actually round because of the pin boss, and they tend to be barrel shaped when cold because the face gets hotter and the skirt expands more. Turbo pistons are also likely forged which further complicates how much they expand. Hopefully someone on one of the Mopar forums still has the information he needs. Once he knows that bore and measures the ring lands he can set about finding rings that will work. Link to comment Share on other sites More sharing options...
85lebaront2 Posted June 24, 2023 Author Share Posted June 24, 2023 I'm sure Bill can mic the pistons but he can't know the alloy or how much they will expand at operating temperature. Venolia would have produced these for a specific bore (within a couple of tenths) Pistons aren't actually round because of the pin boss, and they tend to be barrel shaped when cold because the face gets hotter and the skirt expands more. Turbo pistons are also likely forged which further complicates how much they expand. Hopefully someone on one of the Mopar forums still has the information he needs. Once he knows that bore and measures the ring lands he can set about finding rings that will work. They are first oversize. .5mm or .020" and the ring grooves are standard width for Chrysler. Link to comment Share on other sites More sharing options...
85lebaront2 Posted June 26, 2023 Author Share Posted June 26, 2023 I'm sure Bill can mic the pistons but he can't know the alloy or how much they will expand at operating temperature. Venolia would have produced these for a specific bore (within a couple of tenths) Pistons aren't actually round because of the pin boss, and they tend to be barrel shaped when cold because the face gets hotter and the skirt expands more. Turbo pistons are also likely forged which further complicates how much they expand. Hopefully someone on one of the Mopar forums still has the information he needs. Once he knows that bore and measures the ring lands he can set about finding rings that will work. Back to our regularly scheduled narrative. In bouncing things back and forth with a man who did a serpentine accessory drive system on a 2.2L engine and realizing that due to a number of reasons things are not going to fit the same due to (a) the width of the DOHC head and (b) the front mounted intake manifold. The intake and water outlet occupy the location the AC compressor mounts to, it's mount covers up the area where #1 spark plug goes, leaving it down in a cavity. It also necessitates removal of the AC compressor mount to replace the timing belt. What I initially did was order a VW Jetta balancer, which uses a 6 rib serpentine belt (same width as a lot of Fords). When I made a pilot for my crank gear to the ID of the center hole on the Jetta balancer so it would run true. Assembled the gear and hub assembly to the crank and bolted the balancer on. Slight problem, a lot of axial runout and some radial runout. Took everything off and started looking. I had found that I needed a roughly 7mm spacer inside the gear to line it up with the cam gears, problem, spacer wasn't parallel. I found some washers that would just fit inside the crank gear and could be opened up for the M12X1.5 crank bolt. One probably 4mm thick and one 3mm thick and I have a solid and true running gear and balancer. After doing these, I stuck the head on the block with an MLS gasket like it will be using, tightened the nuts on the ARP studs and went to assemble the timing belt components. With the change from a 40 tooth intermediate shaft gear to a 42 tooth gear, my 150 tooth belt that just would go on, no longer fit, and the 152 tooth fit, but there wasn't enough tensioner range for it to be tight enough. Ok, ordered a 151 tooth belt, just happens to be for a Mitsubishi 4 cyl. Goes on snugly, but auto tensioner adjusts properly. Set it, ran it through probably 25 or 30 cycles, runs nicely on the gears, tensioner doesn't show any sign of uneven running and belt tracks centered on the cam and intermediate gears. The only issue is I am now about 1/2 tooth off on the cams. I went and stuck the head cover, intake manifold, water outlet, distributor and dipstick on for fit, dipstick ends up about 180° from where it goes on the 8 valve head but should be easily accessible where it ended up. Link to comment Share on other sites More sharing options...
Gary Lewis Posted June 27, 2023 Share Posted June 27, 2023 Back to our regularly scheduled narrative. This sounds like two steps forward and one backward. Still progress, but haltingly so. What are you going to do about the cam timing? Off which way? But it is looking like an engine, and that is PROGRESS! Link to comment Share on other sites More sharing options...
85lebaront2 Posted June 27, 2023 Author Share Posted June 27, 2023 Back to our regularly scheduled narrative. This sounds like two steps forward and one backward. Still progress, but haltingly so. What are you going to do about the cam timing? Off which way? But it is looking like an engine, and that is PROGRESS! It is off either retarded or advanced, depending on which way I set the cam gears, I am going to try clamping them at the correct setting and then see if I can get the crank lined up right. The change in the intermediate shaft gear added 2 teeth in it's circumference, or roughly 1 tooth on that side of the belt. Link to comment Share on other sites More sharing options...
Gary Lewis Posted June 27, 2023 Share Posted June 27, 2023 It is off either retarded or advanced, depending on which way I set the cam gears, I am going to try clamping them at the correct setting and then see if I can get the crank lined up right. The change in the intermediate shaft gear added 2 teeth in it's circumference, or roughly 1 tooth on that side of the belt. It is a 42-tooth sprocket on the cams? So you are off 1/84 or 4 degrees. That's a bit much to advance or retard the cams from what I remember. But I'm missing how you might get it lined up on the crank. Offset key? Link to comment Share on other sites More sharing options...
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