My 3B has failed. Short history:
BJ73 overheated on the drive home after purchase(previous mechanic/owner fixed rusted out freeze plug with JB weld which blew out on the highway)..Engine swallowed piece of exhaust valve seat on 2 cylinders scaring the piston dome, but not the bore.
replaced head and smoothed out piston top divits with a small grinder.
Engine ran fine, but decided to turbo for increased power. Had blowby with turbo but got it mostly sorted out. Had good power and EGT's acceptable on level ground on highway. long hills at 90K or medium grades at 110K (with 32" tires and 2" lift) would cause EGT's to head north of 700C and have to slow down. Boost could reach 15PSI uphill.
On a 45min drive at 110K with ambient temp at 90+ degrees on a long uphill the EGT's spiked over 700 for perhaps 20-30seconds before I noticed. After this she was down on power and down to 3cylinders 15 min later when I got home.
No oil in water no water in oil. Compression test numbers 410, 470, 80, 410..........Dropped pan, removed head, removed pistons.......... 2cnd ring broken on 1, 2, and 3. 1st ring on #3 is stuck which in addition to 2cnd ring breakage caused the piston to scrape and wear instead of staying centered. 3 piston crowns are eroded/melted/burned away around the edge between the valve seat indentions.
Crank rod journals are smooth. Will try a "in frame rebuild" new pistons, rings, rod bearings...If I can hone out the minor scoring of #3 bore. If it's too deep I'll have to pull the engine and get it rebored.
There are multiple choices for standard pistons available, mark1-1 mark 2 mark 3 etc. I have looked through the engine manual I have, and haven't found anything in the section on pistons that explains the markings. (or says anything about it for that matter). Under the pistons inside the skirt mine are marked ART _3 on one side and 530850 on the other.
I am considering doing a ceramic heat reflective piston dome coating(cerakote) on the new pistons. Snorkel to get cooler air, ditching the watercooling on the turbo to reduce water temperature, and moving the AC condenser further from the radiator to prevent heat soaking between it and the radiator(current gap is less than .5").
Anyone seen this type of damage before from EGT's, boost, overheat,....Or have any advice on exactly what manual explains the piston markings? The manual I am using is:
BJ73 overheated on the drive home after purchase(previous mechanic/owner fixed rusted out freeze plug with JB weld which blew out on the highway)..Engine swallowed piece of exhaust valve seat on 2 cylinders scaring the piston dome, but not the bore.
replaced head and smoothed out piston top divits with a small grinder.
Engine ran fine, but decided to turbo for increased power. Had blowby with turbo but got it mostly sorted out. Had good power and EGT's acceptable on level ground on highway. long hills at 90K or medium grades at 110K (with 32" tires and 2" lift) would cause EGT's to head north of 700C and have to slow down. Boost could reach 15PSI uphill.
On a 45min drive at 110K with ambient temp at 90+ degrees on a long uphill the EGT's spiked over 700 for perhaps 20-30seconds before I noticed. After this she was down on power and down to 3cylinders 15 min later when I got home.
No oil in water no water in oil. Compression test numbers 410, 470, 80, 410..........Dropped pan, removed head, removed pistons.......... 2cnd ring broken on 1, 2, and 3. 1st ring on #3 is stuck which in addition to 2cnd ring breakage caused the piston to scrape and wear instead of staying centered. 3 piston crowns are eroded/melted/burned away around the edge between the valve seat indentions.
Crank rod journals are smooth. Will try a "in frame rebuild" new pistons, rings, rod bearings...If I can hone out the minor scoring of #3 bore. If it's too deep I'll have to pull the engine and get it rebored.
There are multiple choices for standard pistons available, mark1-1 mark 2 mark 3 etc. I have looked through the engine manual I have, and haven't found anything in the section on pistons that explains the markings. (or says anything about it for that matter). Under the pistons inside the skirt mine are marked ART _3 on one side and 530850 on the other.
I am considering doing a ceramic heat reflective piston dome coating(cerakote) on the new pistons. Snorkel to get cooler air, ditching the watercooling on the turbo to reduce water temperature, and moving the AC condenser further from the radiator to prevent heat soaking between it and the radiator(current gap is less than .5").
Anyone seen this type of damage before from EGT's, boost, overheat,....Or have any advice on exactly what manual explains the piston markings? The manual I am using is: