95RD Posted April 9, 2023 Author Share Posted April 9, 2023 Update - Fuel is turned wide open. - Pryor is installed to watch EGT However I am still having issues producing power. The boost pressure is only getting to 12 psi max (usually stay in around 10 PSI). Having a hard time getting the truck over 60 miles an hour. Max I can get his 65 mph. Next step is to check the cooler for leaks. But I feel like I’m having turbo issues also. Am I correct in saying that the turbo should be producing around 30 psi? Quote Link to comment https://www.bigmacktrucks.com/topic/72622-turn-up-e7/page/2/#findComment-528814 Share on other sites More sharing options...
fjh Posted April 9, 2023 Share Posted April 9, 2023 13 hours ago, 95RD said: Update - Fuel is turned wide open. - Pryor is installed to watch EGT However I am still having issues producing power. The boost pressure is only getting to 12 psi max (usually stay in around 10 PSI). Having a hard time getting the truck over 60 miles an hour. Max I can get his 65 mph. Next step is to check the cooler for leaks. But I feel like I’m having turbo issues also. Am I correct in saying that the turbo should be producing around 30 psi? NO not necessarily! If its not putting out has little smoke then its a fueling issue! If you got a ton of smoke and not putting out then you have a turbo or boost leak issue! if you are not producing alot of smoke you have a fuel problem! when you removed top to slide the fuel plate did you happen to suck or blow on the LDA that you removed? This is the smoke control device ? if the diaphragm has a hole in it , it won't allow the engine to have full fuel! sucking or blowing on the fitting will determine if the diaphragm is OK! If you didn't check this you may have put the cart before the horse! As far as turning it up you only need to slide the plate 10 -20 thou to achieve a big gain on HP! More Fuel The more the boost ! Quote Link to comment https://www.bigmacktrucks.com/topic/72622-turn-up-e7/page/2/#findComment-528849 Share on other sites More sharing options...
95RD Posted April 10, 2023 Author Share Posted April 10, 2023 I checked the diaphragm and it is holding pressure (so no leak). As far as the fuel, we have plenty of fuel going to the engine. It is producing lots of smoke! However the truck is still only producing only 10psi of boost. As far as the LDA. What pressure does it take to activate the fuel rail? If the turbo is only producing 10 psi (max). Is the fuel rail even opening up to supply more fuel to the pump. Also, the truck is strong until it gets to the top gears. Then it falls flat on its face. Does the fuel pump advance its timing as it gets to the top rpm rang? If so, how do you check to see if it is advancing. Quote Link to comment https://www.bigmacktrucks.com/topic/72622-turn-up-e7/page/2/#findComment-528896 Share on other sites More sharing options...
fjh Posted April 10, 2023 Share Posted April 10, 2023 12 hours ago, 95RD said: I checked the diaphragm and it is holding pressure (so no leak). As far as the fuel, we have plenty of fuel going to the engine. It is producing lots of smoke! However the truck is still only producing only 10psi of boost. As far as the LDA. What pressure does it take to activate the fuel rail? If the turbo is only producing 10 psi (max). Is the fuel rail even opening up to supply more fuel to the pump. Also, the truck is strong until it gets to the top gears. Then it falls flat on its face. Does the fuel pump advance its timing as it gets to the top rpm rang? If so, how do you check to see if it is advancing. Test the system for leaks before throwing a turbo at it!the screw under the little cap two (screws ) adjusts the start point for boost build ! Take the little cap off and unlock that jam nut and turn the allen in a half turn to a turn! there is no timing advance on this engine if its mechanical At least non I have seen! It really sounds as thou your chasing a bad boost leak OR bad turbo! THAT SAID ! Check the compressor inlet hose at the manifold and the compressor ! Also I've seen AIR DRiers dump a Guys boost! If All else Fails Temporarily by pass the air drier if it has one ! join the two big hoses together at the bottom ! just something to try before you load the Turbo Ammo Into the parts Cannon ! Quote Link to comment https://www.bigmacktrucks.com/topic/72622-turn-up-e7/page/2/#findComment-528915 Share on other sites More sharing options...
Calvin Posted October 16, 2023 Share Posted October 16, 2023 On 4/4/2023 at 5:09 PM, Joey Mack said: I did have the '95 book... I hope this helps you. Does this manual have the same information for a 1991 E7-350HP VMAC-1? If so, Can you post it? I'm pulling my hair out trying to find this information as someone pulled the data tag off my engine. Thanks in advance Quote Link to comment https://www.bigmacktrucks.com/topic/72622-turn-up-e7/page/2/#findComment-540433 Share on other sites More sharing options...
Joey Mack Posted October 16, 2023 Share Posted October 16, 2023 Well Bud,,, this is the oldest E-7 book i have.. Can you be more specific about what info you want? Its an effort to post lots of pages.. Quote Link to comment https://www.bigmacktrucks.com/topic/72622-turn-up-e7/page/2/#findComment-540437 Share on other sites More sharing options...
Calvin Posted October 16, 2023 Share Posted October 16, 2023 (edited) 54 minutes ago, Joey Mack said: Well Bud,,, this is the oldest E-7 book i have.. Can you be more specific about what info you want? Its an effort to post lots of pages.. I'm looking for the initial injection timing. A follow up question: does the 1994 manual have information only for 1994 model year engines or does it go back a a couple years? Edited October 16, 2023 by Calvin Quote Link to comment https://www.bigmacktrucks.com/topic/72622-turn-up-e7/page/2/#findComment-540438 Share on other sites More sharing options...
Joey Mack Posted October 17, 2023 Share Posted October 17, 2023 is yours full mechanical? the book is for 1994.. I wonder how much is the same? Quote Link to comment https://www.bigmacktrucks.com/topic/72622-turn-up-e7/page/2/#findComment-540439 Share on other sites More sharing options...
Calvin Posted October 17, 2023 Share Posted October 17, 2023 No it's V-MAC 1 so it's electronic controls on the bosch pump. Bosch number 0402 796802 Quote Link to comment https://www.bigmacktrucks.com/topic/72622-turn-up-e7/page/2/#findComment-540440 Share on other sites More sharing options...
Joey Mack Posted October 17, 2023 Share Posted October 17, 2023 I have seen those set around 19 degrees.. I suggest you use the serch feature and try to read some older posts. I cant tell you the answer with confidence.. Jojo Quote Link to comment https://www.bigmacktrucks.com/topic/72622-turn-up-e7/page/2/#findComment-540441 Share on other sites More sharing options...
Calvin Posted October 17, 2023 Share Posted October 17, 2023 (edited) I think 19 is a little high for a V-Mac from my reading. 19 is fine for a fixed timing mechanical E7 , mine is an electronic E7 with the econo-vance, everything I've seen has been said between 5-11, but I have yet to find the timing for my pump, my hp rating on a V-Mac 1 Edited October 17, 2023 by Calvin Quote Link to comment https://www.bigmacktrucks.com/topic/72622-turn-up-e7/page/2/#findComment-540486 Share on other sites More sharing options...
JoeH Posted October 17, 2023 Share Posted October 17, 2023 Looking at E7 tags found on used engines online I've seen 7-18. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/72622-turn-up-e7/page/2/#findComment-540489 Share on other sites More sharing options...
doubleclutchinweasel Posted October 17, 2023 Share Posted October 17, 2023 4 minutes ago, JoeH said: Looking at E7 tags found on used engines online I've seen 7-18. Clever approach! Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/72622-turn-up-e7/page/2/#findComment-540491 Share on other sites More sharing options...
Calvin Posted October 17, 2023 Share Posted October 17, 2023 tried that. I found a tune-up manual on ebay for my year, should have the information. Thanks for the input, gentlemen 1 Quote Link to comment https://www.bigmacktrucks.com/topic/72622-turn-up-e7/page/2/#findComment-540493 Share on other sites More sharing options...
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