RS Disposal Posted December 13, 2023 Author Share Posted December 13, 2023 16 hours ago, JoeH said: Sorry to confuse you with yet another turbo model added to the possibilities. Just rechecked, you're running an ENDTB 675 which will be the 237hp variant! Sorry this turbo is for the 283hp variant! I do have a 237 endt-675 sitting outside my garage, I'll see if it has a tag on it tomorrow! I wou8ld really appreciate that Quote Link to comment https://www.bigmacktrucks.com/topic/73314-looking-for-1979-mack-engine-head/page/7/#findComment-543404 Share on other sites More sharing options...
JoeH Posted December 13, 2023 Share Posted December 13, 2023 5 hours ago, RS Disposal said: I wou8ld really appreciate that Garrett rebuilt turbo. Quote Link to comment https://www.bigmacktrucks.com/topic/73314-looking-for-1979-mack-engine-head/page/7/#findComment-543419 Share on other sites More sharing options...
RS Disposal Posted December 13, 2023 Author Share Posted December 13, 2023 22 hours ago, JoeH said: Can you post a picture of the exhaust side of your engine? I have 2 endt675 motors, one from a U model the other is in an R model. I think the exhaust manifolds are the same, but seeing yours will help me compare to the U model I have. Quote Link to comment https://www.bigmacktrucks.com/topic/73314-looking-for-1979-mack-engine-head/page/7/#findComment-543422 Share on other sites More sharing options...
JoeH Posted December 13, 2023 Share Posted December 13, 2023 Took me a minute to figure out what that things in! That's a cabover, not sure what model truck. Your exhaust is a different layout than mine. There should be a tag between the two halves of the turbo. May need to crawl deep in there and clean it off. Quote Link to comment https://www.bigmacktrucks.com/topic/73314-looking-for-1979-mack-engine-head/page/7/#findComment-543424 Share on other sites More sharing options...
RS Disposal Posted December 13, 2023 Author Share Posted December 13, 2023 4 minutes ago, JoeH said: Took me a minute to figure out what that things in! That's a cabover, not sure what model truck. Your exhaust is a different layout than mine. There should be a tag between the two halves of the turbo. May need to crawl deep in there and clean it off. Quote Link to comment https://www.bigmacktrucks.com/topic/73314-looking-for-1979-mack-engine-head/page/7/#findComment-543425 Share on other sites More sharing options...
RS Disposal Posted December 13, 2023 Author Share Posted December 13, 2023 Just now, RS Disposal said: this is a cab over garbage truck. The VIN shows it as a box truck according to the dealer Quote Link to comment https://www.bigmacktrucks.com/topic/73314-looking-for-1979-mack-engine-head/page/7/#findComment-543426 Share on other sites More sharing options...
RS Disposal Posted December 17, 2023 Author Share Posted December 17, 2023 Well, after 4 disappointments on getting a rebuilt turbo I was finally able to get one and get it installed. According to the rebuilder it specs out to be the same as my original, but the compressor housing is larger in diameter, although narrower in width, which presented a couple of minor problems in installing. I had to undo a frame strut and also install a 1/4 inch spacer because the housing would hit a bolt on the rear of the engine. Other than that, everything seemed to line up ok. When I have the engine running at idle I am picking up noises that I don't remember hearing before. Not bad noises I'm pretty sure. Most likely I am thinking I am just being much more intense in my listening than before because of the major breakdown I just had to repair. It has been a tough and interesting journey for the 3 1/2 months my truck was down. Tomorrow she goes back into service with my fingers crossed. On another note, I decided to install a boost gauge, which it never had before, and was wondering what kind of boost pressures I would be looking at and whether or not the slight differences in the turbo compressor housing would have any great effect on that. I also decided to reinstall a pyrometer, which it did have years ago but when some exhaust work was done at one time the sender was never reinstalled and being the original is no longer available, I put in an aftermarket. A sticker in the cab by the original gauge states 1125 degrees (I think) max. Is this about what I would be looking at. My other truck does have both of those gauges, but it is a much larger motor (Cummins N14) and off hand I don't remember what it would run on those gauges anyway. Also, if anyone out there might need, I do have a new in box Mack 185606 CHRA and a never installed rebuilt 4LE-292 turbo, both of which I purchased in my trek of trying to get something that would work. I will post here how the truck does on her first day back to work. I want to THANK everyone here for all your help and guidance, this forum has been invaluable in my learning experience. Quote Link to comment https://www.bigmacktrucks.com/topic/73314-looking-for-1979-mack-engine-head/page/7/#findComment-543595 Share on other sites More sharing options...
Joey Mack Posted December 17, 2023 Share Posted December 17, 2023 Good deal, and good luck,, 25-30 PSI Boost.. I cant give you an exact PSI.. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73314-looking-for-1979-mack-engine-head/page/7/#findComment-543598 Share on other sites More sharing options...
JoeH Posted December 17, 2023 Share Posted December 17, 2023 Around 10-15 psi is when the 283hp version kicks into the power band and really starts pulling. My gauge I added on my '79 endt676 only went to 25 psi and it pegs that pretty well. Not sure what the endt675 237hp motor does. Probably similar. 2 Quote Link to comment https://www.bigmacktrucks.com/topic/73314-looking-for-1979-mack-engine-head/page/7/#findComment-543599 Share on other sites More sharing options...
Joey Mack Posted December 17, 2023 Share Posted December 17, 2023 That makes sense, it is an E-6.. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73314-looking-for-1979-mack-engine-head/page/7/#findComment-543600 Share on other sites More sharing options...
RS Disposal Posted December 31, 2023 Author Share Posted December 31, 2023 truck is back to work and appears to be running ok. Only issue, which started last summer before it died, is it gets hot climbing the canyon where most of my pickups are. Canyon is between 6 - 9% grade and 8 miles long. I just watch engine temp and stop and let it cool, which it does within 5-10 minutes at idle, and continue on. In the valley it runs between 180 & 190 all day long. Pretty sure radiator needs to be rodded out. Nothing has ever been done to it since new and truck is 1979. Will have to just watch engine temp until my slow season before I can take it out of service for several days or so again. I think at the same time just for shits and giggles replace water pump, fan clutch and thermostat. Here is another newby question as far as turbocharged big diesel engines. As far as the turbo boost is concerned, what exactly determines the amount of boost you get? Is it the diameter of the compressor housing? New turbo compressor housing is larger in diameter, but also not as wide as original. This truck has never had a boost gauge, so I have no comparison to go by. Around town I am running between 6-10 lbs boost. When climbing canyon I can get as high as 18-20 lbs boost. Climbing canyon pyrometer shows 600 - 700 degrees and around town 400 - 500 degrees. Sticker on the original gauge says max temp is 1125 and it doesn't get anywhere near that and the sensor is in the same place as original. Again I want to thank everyone for their help and insight that was given on my learning experience over the last several months. Here's wish each and everyone of you a joyous new year and wishes for a great year to come. Quote Link to comment https://www.bigmacktrucks.com/topic/73314-looking-for-1979-mack-engine-head/page/7/#findComment-544403 Share on other sites More sharing options...
JoeH Posted January 1 Share Posted January 1 What are you seeing on radiator temps climbing the canyon? You can ditch the clutch for a solid fan. If you're getting any belt squeal whatsoever then tighten your belt a little, that may help with staying cool. My E7-350 would run hot and squeal a bit at slower speeds/higher RPM. Tightened the belt and it runs cooler. My '79 also lists 1125 as max on pyro, not sure we ever hit it though. The engine is ready to downshift before it gets that hot. Quote Link to comment https://www.bigmacktrucks.com/topic/73314-looking-for-1979-mack-engine-head/page/7/#findComment-544426 Share on other sites More sharing options...
mrsmackpaul Posted January 1 Share Posted January 1 A tipturbine motor is about 17 psi max Pyro only gets up there on big looooooong pulls, not steep hills but big gentle pulls for many miles Or at least thats my experience Paul Quote Link to comment https://www.bigmacktrucks.com/topic/73314-looking-for-1979-mack-engine-head/page/7/#findComment-544438 Share on other sites More sharing options...
RS Disposal Posted January 1 Author Share Posted January 1 15 hours ago, JoeH said: What are you seeing on radiator temps climbing the canyon? You can ditch the clutch for a solid fan. If you're getting any belt squeal whatsoever then tighten your belt a little, that may help with staying cool. My E7-350 would run hot and squeal a bit at slower speeds/higher RPM. Tightened the belt and it runs cooler. My '79 also lists 1125 as max on pyro, not sure we ever hit it though. The engine is ready to downshift before it gets that hot. I will use my heat gun tonite when I go back up canyon and check radiator temp. I stop to let cool once my temp gauge hits about 220. Quote Link to comment https://www.bigmacktrucks.com/topic/73314-looking-for-1979-mack-engine-head/page/7/#findComment-544482 Share on other sites More sharing options...
JoeH Posted January 1 Share Posted January 1 220 is too hot. Water boils at 212. What RPMs are you running when it gets that hot? You need to keep engine speed up to keep fan spinning and air flowing through the heads. Quote Link to comment https://www.bigmacktrucks.com/topic/73314-looking-for-1979-mack-engine-head/page/7/#findComment-544486 Share on other sites More sharing options...
terry Posted January 1 Share Posted January 1 If the water temperature was that hot, wouldn’t the exhaust temps. Be higher? Terry Quote Link to comment https://www.bigmacktrucks.com/topic/73314-looking-for-1979-mack-engine-head/page/7/#findComment-544498 Share on other sites More sharing options...
Geoff Weeks Posted January 1 Share Posted January 1 For what it is worth, address the heat issue, start with the radiator, if you can find a good shop anymore. I put a new rad in my truck that I always had to watch the temp on. Shortly there after I was pulling a full load over the Big Horn mts. 45 min at full throttle and 25 MPH! That will test any radiator! Anytime you can't run full power for extended period of time, you have a problem, and it will only get worse. The radiator only has to drop the coolant temp 10 deg from inlet to outlet to keep the engine cool. If it can't do that, it is telling you where the problem is. 2 Quote Link to comment https://www.bigmacktrucks.com/topic/73314-looking-for-1979-mack-engine-head/page/7/#findComment-544501 Share on other sites More sharing options...
RS Disposal Posted January 2 Author Share Posted January 2 (edited) Just now, JoeH said: 220 is too hot. Water boils at 212. What RPMs are you running when it gets that hot? You need to keep engine speed up to keep fan spinning and air flowing through the heads. Running a 15 lb radiator cap RPM's are around 1800. I can run around town all day long and engine runs around 180-190 according to the temp gauge Edited January 2 by RS Disposal Quote Link to comment https://www.bigmacktrucks.com/topic/73314-looking-for-1979-mack-engine-head/page/7/#findComment-544540 Share on other sites More sharing options...
RS Disposal Posted January 2 Author Share Posted January 2 Well I forgot my heat gun this morning so that will have to wait But I had another issue arise just after I came down the canyon with a load on. I am getting what I can best describe is a pulsating noise coming from the air filter intake. The boost gauge flutters. As to how much depends on throttle position. Haven't had the chance to tilt cab yet and look around. What might I be looking for? Could a rubber hose come loose or cracked? There are several between the turbo and intake manifold. The engine seems to still be running smooth. Seems I just can't catch a break and have just entered into my busy season Quote Link to comment https://www.bigmacktrucks.com/topic/73314-looking-for-1979-mack-engine-head/page/7/#findComment-544541 Share on other sites More sharing options...
mrsmackpaul Posted January 2 Share Posted January 2 Compressor??? Does it suck from the intake ? If you can maintain 1800 revs on a climb your not over loading it at all Guessing as you suggested, it might be time to rod the radiator out A dipstick from a automatic transmission works well, no sharp edges Paul Quote Link to comment https://www.bigmacktrucks.com/topic/73314-looking-for-1979-mack-engine-head/page/7/#findComment-544543 Share on other sites More sharing options...
RS Disposal Posted January 2 Author Share Posted January 2 (edited) started the engine with the tube from the turbo removed. Sounded like a popping noise coming out of the intake manifold. was thinking thaty for some reason maybe an intake valve wasn't closing all the way. Took rocker cover off and double check my valve lash. Some of the exhaust were a little loose.. Now when I start it it smokes (white smoke) really bad and idle rough. What the crap did I do? If I tightened the exhaust too tight would that cause the smoking? So dang hard to gauge TDC and rotating engine 1/4 turn. Edited January 2 by RS Disposal Quote Link to comment https://www.bigmacktrucks.com/topic/73314-looking-for-1979-mack-engine-head/page/7/#findComment-544545 Share on other sites More sharing options...
mrsmackpaul Posted January 2 Share Posted January 2 White smoke to me is either timing or air in the fuel People smarter than will have better answers Did you have the cam out or timing changed Maybe something has come loose and shifted Paul Quote Link to comment https://www.bigmacktrucks.com/topic/73314-looking-for-1979-mack-engine-head/page/7/#findComment-544547 Share on other sites More sharing options...
RS Disposal Posted January 2 Author Share Posted January 2 Just now, mrsmackpaul said: White smoke to me is either timing or air in the fuel People smarter than will have better answers Did you have the cam out or timing changed Maybe something has come loose and shifted Paul cam was never removed. just the rear head. And the stinking truck was running so good too. Was gonna kinda pat myself on the back for a job well done. Guess I spoke too soon Quote Link to comment https://www.bigmacktrucks.com/topic/73314-looking-for-1979-mack-engine-head/page/7/#findComment-544548 Share on other sites More sharing options...
RS Disposal Posted January 3 Author Share Posted January 3 another quick question. The truck was running good up until this point. I was double checking my valve lash and did find some that were out of spec. I may of not actually had the Piston at true TDC. After some clean u9p I was able to find the marks on the vibration dampener at the 120 degree spacing. Readjusted everything using these marks and the truck seems to be back to normal. Question is, "why the hiccup"? Quote Link to comment https://www.bigmacktrucks.com/topic/73314-looking-for-1979-mack-engine-head/page/7/#findComment-544576 Share on other sites More sharing options...
RS Disposal Posted January 3 Author Share Posted January 3 20 hours ago, mrsmackpaul said: Compressor??? Does it suck from the intake ? If you can maintain 1800 revs on a climb your not over loading it at all Guessing as you suggested, it might be time to rod the radiator out A dipstick from a automatic transmission works well, no sharp edges Paul I think when it comes time to do the radiator I will take it into a local shop that does heavy truck radiators. I don't have the expertise or tools to do the soldering of this brass radiator Quote Link to comment https://www.bigmacktrucks.com/topic/73314-looking-for-1979-mack-engine-head/page/7/#findComment-544577 Share on other sites More sharing options...
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