Gst 7.7 wont start
#1
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From: monroe,
MI
Hey all..
I got a CEN gst 7.7 in a trade for my revo. I have always wanted one of these trucks due to thier reputation, size and looks..
I get up yesterday just in time to catch the mail lady and there is it waiting for me. So i excitedly open the box to reveal the massive truck and head on the .46 engine. I put fresh batteries in it, and checked it all out, exactly as stated. So i filled her up with 20% nitro made sure the glow plug worked and went at it..
Well, I tried for over an hour to get this truck to start, it has a rotostart on it, and i used up my rotostarter battery twice, and my 18v drill battery. I tried priming it through the carb, changing glow plugs, cracking the glow plug, heating the head with a hairdryer, you name it i tried it. Around 1/2 way through my little adventure i heard a squeaking when it was turning over, if i went slow it didnt do it. If i went full speed it did. Maybe the one way bearing, but it was still catching and turning the motor over. I used one of those big 1.5 batteries for my glow plug igniter and i know that wasnt dead, i even tested both gp's before even trying to start it.
I want to keep this truck and have been dying to get one.. Is there some sort of trick to starting this beast so i can go have fun with it? or am i doing something wrong. I did try using the radio to open the carb about 20% and going back and forth just seemed like it didnt even want to fire..
Any help will be appreciated
I got a CEN gst 7.7 in a trade for my revo. I have always wanted one of these trucks due to thier reputation, size and looks..
I get up yesterday just in time to catch the mail lady and there is it waiting for me. So i excitedly open the box to reveal the massive truck and head on the .46 engine. I put fresh batteries in it, and checked it all out, exactly as stated. So i filled her up with 20% nitro made sure the glow plug worked and went at it..
Well, I tried for over an hour to get this truck to start, it has a rotostart on it, and i used up my rotostarter battery twice, and my 18v drill battery. I tried priming it through the carb, changing glow plugs, cracking the glow plug, heating the head with a hairdryer, you name it i tried it. Around 1/2 way through my little adventure i heard a squeaking when it was turning over, if i went slow it didnt do it. If i went full speed it did. Maybe the one way bearing, but it was still catching and turning the motor over. I used one of those big 1.5 batteries for my glow plug igniter and i know that wasnt dead, i even tested both gp's before even trying to start it.
I want to keep this truck and have been dying to get one.. Is there some sort of trick to starting this beast so i can go have fun with it? or am i doing something wrong. I did try using the radio to open the carb about 20% and going back and forth just seemed like it didnt even want to fire..
Any help will be appreciated
#2
First of all do you know and trust the person you got it from?
Second try setting the carb back to factory settings then try restarting
[link=http://www.cenracing.com/downloads/Engine%20Doc%20NX76.doc]The Factory Settings Can Be Seen Here!! [/link]
Try that, let us know..
Second try setting the carb back to factory settings then try restarting
[link=http://www.cenracing.com/downloads/Engine%20Doc%20NX76.doc]The Factory Settings Can Be Seen Here!! [/link]
Try that, let us know..
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From: monroe,
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okay i will try to set it back to factory settings, i trust the guy i got it from he was on top of everything and did exactly what i needed. I am getting a new o.s. A5 glow plug today, and i am getting the new exhaust gasket we can go from there and ill set it to factory specs.
Oh and fast where can i find that writeup on cens website
Oh and fast where can i find that writeup on cens website
#6
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From: City of Industry,
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Check all the screws and nuts to insure they are tight. Put a fresh glow plug in there when you go back to factory settings you may want to consider increasing the idle as well. Always remember to prime the engine just a few tugs on the p.s. while pluging the exhaust tip with a rag.
#7
I run O.S. 8 plugs and even when the truck sit's months, with after run oil, it starts in 2-4 pulls almost every time. I just put my finger on the exust port, pull 2-3 pops, put the glow starter on and a few short yanks later I'm off.
How many gallons did he run? Like TRD said, start from factory settings and we'll work from there.
Since your new to the truck, make sure you have a one way valve from the exhaust TO the tank to solve the half tank lean issue we all have. Unless you have a 175cc tank or smaller on it(I think that's the largest I've seen without problems).
Good luck, once you get it running you'll love the truck, it's a beast.
How many gallons did he run? Like TRD said, start from factory settings and we'll work from there.
Since your new to the truck, make sure you have a one way valve from the exhaust TO the tank to solve the half tank lean issue we all have. Unless you have a 175cc tank or smaller on it(I think that's the largest I've seen without problems).
Good luck, once you get it running you'll love the truck, it's a beast.
#8
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From: monroe,
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Well i went out and bought the A5 plug, its about 72 degrees so it should have been fine, replaced the exhaust gasket and fuel lines.. still will not push fuel through the fuel lines by putting my finger over the exhaust. I belive it has the 220cc fuel cell. I dont know what kind of one way or check valve i should put in or where to get one, and i imagine its supposed to go between the cell and the engine.
I finally broke down and called CEN let me tell you they have amazing tech support. I told the guy my situation and he went through some needle adjustments and different things to do to it while im on the phone. End result, he is going to have me send the engine to him in california and replace all the bad parts or anything thats wrong with it, and maybe put a pullstarter on it for me.. He is going to fix it under warranty due to my situation. I hope he can get that bad boy to work for me, and he said he'd fix it the day he got it and send it back out.. we will see how that goes.. so far CEN gets an a+ in the customer service department.
I finally broke down and called CEN let me tell you they have amazing tech support. I told the guy my situation and he went through some needle adjustments and different things to do to it while im on the phone. End result, he is going to have me send the engine to him in california and replace all the bad parts or anything thats wrong with it, and maybe put a pullstarter on it for me.. He is going to fix it under warranty due to my situation. I hope he can get that bad boy to work for me, and he said he'd fix it the day he got it and send it back out.. we will see how that goes.. so far CEN gets an a+ in the customer service department.
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From: monroe,
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yeah the guys name was chris.. he went through alot of steps with me to try and get it to start. and even asked if my neighbors minded if i started the truck LOL.. He told me all i had to do was pay to ship it there, and when he got it he would look at it the day he got it and give me FREE parts and labor, and do it all under warranty since i just got the truck even in a trade and what not. I asked how long, he just told me ship it priority mail, and he will send it back to me the day after he gets it and fixes it. Even though I havent played with the truck, i really feel comfortable with the customer support being so nice. and i didnt even have to wait 30 seconds to speak with a live person and tell him the situation hopefully he can get something done about it for me and get it all fixed if anything is wrong. Thanks for all the help on here though, its really nice to have a forum to come to and get different opinions and what not
Brian
Brian
#12
ORIGINAL: delray226
I dont know what kind of one way or check valve i should put in or where to get one, and i imagine its supposed to go between the cell and the engine.
I dont know what kind of one way or check valve i should put in or where to get one, and i imagine its supposed to go between the cell and the engine.
Glad to hear everything worked out for you. Hope it's in your hands soon.
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From: monroe,
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yup i got the stock tank.. I will pick up an ofna check valve this weekend when im up near the LHS and install it. Maybe it will help my problem too.. I hope everything works right with CEN i just shipped it today would u guys like me to keep you posted on how it goes?
Burningpoo: thanks so much for the pictures and the explanation of that i really appreciate it
Burningpoo: thanks so much for the pictures and the explanation of that i really appreciate it
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From: monroe,
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just a quick update for all of you.. I got the engine back from cen. he put a pullstart on it, send me back my rotostart, replaced my manifold gasket, and spring. Got it in the truck... 2 pulls she started right up!! Now to mess with those pesky shift points.. EHh and im noticing when my tank is about half full.. the truck will stall out if i get on it.. Also it doesnt like to steer very well. I dont know why, but it seems to have trouble turning. i put fresh batteries in it and everything, When driving it seems to go wide when turning.. anyone have any ideas?
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From: Niagara Falls, ON, CANADA
ORIGINAL: delray226
just a quick update for all of you.. I got the engine back from cen. he put a pullstart on it, send me back my rotostart, replaced my manifold gasket, and spring. Got it in the truck... 2 pulls she started right up!! Now to mess with those pesky shift points.. EHh and im noticing when my tank is about half full.. the truck will stall out if i get on it.. Also it doesnt like to steer very well. I dont know why, but it seems to have trouble turning. i put fresh batteries in it and everything, When driving it seems to go wide when turning.. anyone have any ideas?
just a quick update for all of you.. I got the engine back from cen. he put a pullstart on it, send me back my rotostart, replaced my manifold gasket, and spring. Got it in the truck... 2 pulls she started right up!! Now to mess with those pesky shift points.. EHh and im noticing when my tank is about half full.. the truck will stall out if i get on it.. Also it doesnt like to steer very well. I dont know why, but it seems to have trouble turning. i put fresh batteries in it and everything, When driving it seems to go wide when turning.. anyone have any ideas?
The tank half full stalling thing can be corrected by using the Ofna primer pump/check valve, that Burningpoo suggested you get, did you purchase/install this? If you havent be aware that you will have to retune the truck significantly.
The stock steering servo on the GST is not really up to the task of pushing the huge GST wheels, there are two methods that are being used to fix this: 1. Get a stonger servo, most people use the Hitec 5955TG servo, this will turn the wheels nicely for you. 2. Dogmans dual servo steering mod (see sticky at the top of the forum), however this requires a bit of work to complete, its not a bolt on affair. Also something you should consider getting is a good quality battery pack, they tend to provide more power then regular batteries, you should notice a difference.
Good luck




