JoeH Posted January 20 Share Posted January 20 On the ETECH motors I think I've heard that the lower exhaust manifold bolts are open to the pushrod passageways, so you can get oil coming through the stud threads. Probably not part of the issue, but maybe? 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73764-e7-rebuild-q/page/2/#findComment-545377 Share on other sites More sharing options...
Joey Mack Posted January 20 Share Posted January 20 yes, the lower exhaust stud holes are open. they go into the pushrod bore.. with this being said, if you re-seal/replace them be sure to avoid running those studs too deep. you WILL hit the pushrod.. the stud end in the head is about 3/4''.. if you decide to pull the heads, before you do, get a dozen M16 x 75mm long bolts, and large washers the same size as a half dollar. you will use these to hold the liners down. this way when you are rotating the crank to inspect the liners, you wont risk the chance of moving a liner. It's rare, but possible.. Jojo 1 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73764-e7-rebuild-q/page/2/#findComment-545381 Share on other sites More sharing options...
JoeH Posted January 20 Share Posted January 20 3 minutes ago, Joey Mack said: yes, the lower exhaust stud holes are open. they go into the pushrod bore.. with this being said, if you re-seal/replace them be sure to avoid running those studs too deep. you WILL hit the pushrod.. the stud end in the head is about 3/4''.. if you decide to pull the heads, before you do, get a dozen M16 x 75mm long bolts, and large washers the same size as a half dollar. you will use these to hold the liners down. this way when you are rotating the crank to inspect the liners, you wont risk the chance of moving a liner. It's rare, but possible.. Jojo He is working on an E7 mechanical, not sure if the heads are the same as the E7 ETECH engines. Do the older E7's have this exhaust stud issue too? Quote Link to comment https://www.bigmacktrucks.com/topic/73764-e7-rebuild-q/page/2/#findComment-545382 Share on other sites More sharing options...
Joey Mack Posted January 20 Share Posted January 20 yes,, especially in re-man heads.. I think they werent fully drilled through and you can punch out the slug if you put the stud in too far.. I think i remember that 🤔 2 Quote Link to comment https://www.bigmacktrucks.com/topic/73764-e7-rebuild-q/page/2/#findComment-545391 Share on other sites More sharing options...
fjh Posted January 21 Share Posted January 21 On 1/19/2024 at 4:32 PM, Joey Mack said: just look at cross hatching.. if there is some left, just hone them and GO!.. the new rings will make up the difference. it will run fine.. you may have to trim the carbon ridge at the top of the liner, but that is common for liner re-use.. before you pull the heads, come back for more advice.. exactly the route I would take if I was in your shoes!pop the heads off in a lump don’t take everything apart leave manifolds on! Pull the pan pop out the pistons ball hone the liners be careful not to hit piston coolers new rod and mains re ring and reassemble!likely cost a lot less than ten k and worth the effort in your case and if it goes sideways in a few years you aren’t out much! 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73764-e7-rebuild-q/page/2/#findComment-545404 Share on other sites More sharing options...
JoeH Posted January 21 Share Posted January 21 If you're doing the heads yourself, DONT SWT THEM DOWN "RIGHT SIDE UP"! The injector nozzles stick down into the combustion chamber, you'll crush the tips! Either set them down on cribbing or set them down on their side. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73764-e7-rebuild-q/page/2/#findComment-545408 Share on other sites More sharing options...
Straydog954 Posted January 21 Author Share Posted January 21 All good tips, thanks. Also does worn rings contribute to lower boost pressure? I can only get like 23 tops and that’s going up a grade with a 20 load workin its ass off. I’ve read about other things posted on this site that causes low boost and I will check those. Seems like people with e7s on here talk about getting 28-30 or more but maybe that’s with larger turbo and injectors etc. Quote Link to comment https://www.bigmacktrucks.com/topic/73764-e7-rebuild-q/page/2/#findComment-545409 Share on other sites More sharing options...
fjh Posted January 21 Share Posted January 21 47 minutes ago, Straydog954 said: All good tips, thanks. Also does worn rings contribute to lower boost pressure? I can only get like 23 tops and that’s going up a grade with a 20 load workin its ass off. I’ve read about other things posted on this site that causes low boost and I will check those. Seems like people with e7s on here talk about getting 28-30 or more but maybe that’s with larger turbo and injectors etc. It can contribute! A strong/ fresh 350 25 - 28 psi / 460 33 - 38 ! If your trailing Smoke under a pull you may have a boost leak, another symptom is if you have a pyrometer it will raise quick! Can't emphasize enough ! You have to take in to account the age and what's worth spending for what your doing! oil is cheap in some ways! just stuff to consider! 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73764-e7-rebuild-q/page/2/#findComment-545412 Share on other sites More sharing options...
Straydog954 Posted January 21 Author Share Posted January 21 1 hour ago, fjh said: It can contribute! A strong/ fresh 350 25 - 28 psi / 460 33 - 38 ! If your trailing Smoke under a pull you may have a boost leak, another symptom is if you have a pyrometer it will raise quick! Can't emphasize enough ! You have to take in to account the age and what's worth spending for what your doing! oil is cheap in some ways! just stuff to consider! I hear ya loud n clear. I decide I’m gonna run this thing thru a shop and give it a new set of nutz! Need to work this truck another 10 yrs minimum. Tired of the blow by fumes in the cab. Will repost at a later date with results. Thanks everyone for the posts Quote Link to comment https://www.bigmacktrucks.com/topic/73764-e7-rebuild-q/page/2/#findComment-545414 Share on other sites More sharing options...
JoeH Posted January 21 Share Posted January 21 What cab is this truck, RD690? You could have a fatigue crack on the charge air cooler, my 95 e7-350 had one running most of the way down the passenger side. My truck made 25 psi ever since we bought it in 2009, ran hot on the pyro too. Last year it started dipping closer to 22 psi max. Found the cracked CAC, put a new one on and now I get 34 psi on a good pull, and cooler pyro temps. Rarely over 900 degrees now. 2 Quote Link to comment https://www.bigmacktrucks.com/topic/73764-e7-rebuild-q/page/2/#findComment-545417 Share on other sites More sharing options...
fjh Posted January 21 Share Posted January 21 23 minutes ago, JoeH said: What cab is this truck, RD690? You could have a fatigue crack on the charge air cooler, my 95 e7-350 had one running most of the way down the passenger side. My truck made 25 psi ever since we bought it in 2009, ran hot on the pyro too. Last year it started dipping closer to 22 psi max. Found the cracked CAC, put a new one on and now I get 34 psi on a good pull, and cooler pyro temps. Rarely over 900 degrees now. That’s exceptional boost for a 350 your fortunate! 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73764-e7-rebuild-q/page/2/#findComment-545418 Share on other sites More sharing options...
Straydog954 Posted January 21 Author Share Posted January 21 21 minutes ago, JoeH said: What cab is this truck, RD690? You could have a fatigue crack on the charge air cooler, my 95 e7-350 had one running most of the way down the passenger side. My truck made 25 psi ever since we bought it in 2009, ran hot on the pyro too. Last year it started dipping closer to 22 psi max. Found the cracked CAC, put a new one on and now I get 34 psi on a good pull, and cooler pyro temps. Rarely over 900 degrees now. Yes 96 RD690. Truck doesn’t have a pyro. but I need to get one. I will have to look for cracks. I also read where you can cap off both ends of CAC and put 20lbs of air or so in it and put it in a tub of water to find any leaks. Quote Link to comment https://www.bigmacktrucks.com/topic/73764-e7-rebuild-q/page/2/#findComment-545419 Share on other sites More sharing options...
Joey Mack Posted January 21 Share Posted January 21 you dont have to remove the CAC. just spray with soapy water.. there usually crack on the right side near the top and along the weld on the tank.. Just like Joeh said. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73764-e7-rebuild-q/page/2/#findComment-545422 Share on other sites More sharing options...
JoeH Posted January 21 Share Posted January 21 Just had my plugs out the other day, I forget if it's 3 or 4 inch, schedule 40 PVC pipe caps from home Depot. Plugs right into the rubber boots on the CAC. Drill one and put a wheel valve stem in it. Should be good for 35 psi, if it leaks you'll know quick. Quote Link to comment https://www.bigmacktrucks.com/topic/73764-e7-rebuild-q/page/2/#findComment-545427 Share on other sites More sharing options...
Joey Mack Posted January 21 Share Posted January 21 Well Straydog, I appreciate the fact that you want to get it re-built.. Please make sure the shop knows how to do Mack engines. especially setting the liners to the correct height. and ask if they have a counter bore cutter in the case the shelves are pitted out to the edge. Quote Link to comment https://www.bigmacktrucks.com/topic/73764-e7-rebuild-q/page/2/#findComment-545430 Share on other sites More sharing options...
Straydog954 Posted January 21 Author Share Posted January 21 14 minutes ago, Joey Mack said: Well Straydog, I appreciate the fact that you want to get it re-built.. Please make sure the shop knows how to do Mack engines. especially setting the liners to the correct height. and ask if they have a counter bore cutter in the case the shelves are pitted out to the edge. Yes sir will do. I’m not going to miss the little extra money spent. Either way I will still be sleeping in the same house and driving the same pickup. May just have to hide the checkbook for a little bit……. 2 Quote Link to comment https://www.bigmacktrucks.com/topic/73764-e7-rebuild-q/page/2/#findComment-545433 Share on other sites More sharing options...
Joey Mack Posted January 21 Share Posted January 21 I wish you the Best !! Jojo keep us posted.. Quote Link to comment https://www.bigmacktrucks.com/topic/73764-e7-rebuild-q/page/2/#findComment-545434 Share on other sites More sharing options...
fjh Posted January 21 Share Posted January 21 1 minute ago, Joey Mack said: I wish you the Best !! Jojo keep us posted.. Yup agree keep us posted! Quote Link to comment https://www.bigmacktrucks.com/topic/73764-e7-rebuild-q/page/2/#findComment-545435 Share on other sites More sharing options...
880joe Posted January 21 Share Posted January 21 A PAI pistonless inframe kit was only around $1200 last time I checked that's what I would do if it were mine 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73764-e7-rebuild-q/page/2/#findComment-545437 Share on other sites More sharing options...
fjh Posted January 21 Share Posted January 21 1 hour ago, Joey Mack said: Well Straydog, I appreciate the fact that you want to get it re-built.. Please make sure the shop knows how to do Mack engines. especially setting the liners to the correct height. and ask if they have a counter bore cutter in the case the shelves are pitted out to the edge. What he said!😃liner height over 24 -28 is best! Quote Link to comment https://www.bigmacktrucks.com/topic/73764-e7-rebuild-q/page/2/#findComment-545439 Share on other sites More sharing options...
Popular Post Straydog954 Posted January 21 Author Popular Post Share Posted January 21 9 minutes ago, 880joe said: A PAI pistonless inframe kit was only around $1200 last time I checked that's what I would do if it were mine Yes that is what other members were thinking was probably most practical for what the truck is. I’m going to have it opened up by a competent shop and proceed based on what everything looks like. 2 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73764-e7-rebuild-q/page/2/#findComment-545440 Share on other sites More sharing options...
Straydog954 Posted January 22 Author Share Posted January 22 Is it advisable to change oil pump at this time also? Quote Link to comment https://www.bigmacktrucks.com/topic/73764-e7-rebuild-q/page/2/#findComment-545453 Share on other sites More sharing options...
Joey Mack Posted January 22 Share Posted January 22 Yes. However there is a spec for re- use.. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73764-e7-rebuild-q/page/2/#findComment-545454 Share on other sites More sharing options...
Straydog954 Posted January 22 Author Share Posted January 22 5 hours ago, Joey Mack said: Yes. However there is a spec for re- use.. I’m going with a high volume pump because I’m adding a Jake to this engine. I can go Remack or new PAI? Any difference here? Remack would be less money Quote Link to comment https://www.bigmacktrucks.com/topic/73764-e7-rebuild-q/page/2/#findComment-545463 Share on other sites More sharing options...
JoeH Posted January 22 Share Posted January 22 My CAC testing kit. Two 3 inch PVC pipe caps from Home Depot, one with a wheel valve stem for pressurizing. Third fitting is a 2 inch cap wrapped in electrical tape to make the difference to the 3" required by my MR688S. Uses a different size CAC outlet than my RD688S. Just tossing this out there into the Abyss of BigMackTrucks info. 1 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73764-e7-rebuild-q/page/2/#findComment-545465 Share on other sites More sharing options...
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