Im running a kohler 27 PD front mounted gas tanks. At idle if I dump the throttle and give it wide open throttle the motor strains like its starving for gas and will die if I don't let off throttle even then sometimes it does. Also, it will struggle when running full throttle and the primer bulb will normally no longer be primed. While idling it I continually pump the bulb the normally doesn't strain, however if not careful the motor will flood. I've contacted PD they said it would most likely be trash I've looked and haven't seen any trash or water. I assumed a fuel pump would fix it, but unsure how to instal or if it's the solution. PD said tey doubted it needed a elec. fuel pump. This is my first mud motor so im a little hesitant to start messing with it too much. Trying to get it running right before duck season any help would be greatly appreciated.

You never really "need" an electric fuel pump. Most people running them had another issue that they could not track down.

Sounds like trash in your carb or possibly an air leak in your fuel line.

I've replaced the hose I noticed when running from the gas tank up front the motor doesn't run as good as when today I ran a shorter hose with tank in the back. However, I still noticed the same issue just doesn't seem as bad. E

What all are you running in line? Quick connects, filters, primer bulb, etc? Chances are one of your connections is just not tight.

9mm I.D. Fuel line in beginning was hooked straight to tank with clamps, primer bulb hooked up to fuel filter. Had issue and wanted to run a smaller tank so added quick connects with same set up. However today I ran a 9.5mm line hooked straight to fuel filter with tank in back of boat ran about the same maybe a little better but not much.

9 mm? You in Canada?

If you are confident there is no air leaks, clean your carb. Go to the kohler website and download the users and service manual. It'll have diagrams and instructions. You need to pull the jets, and blow them out.

Lol no Arkansas...the 9mm was what was run when I purchased the rig lol. I'll see if I can figure that out lol. Thanks for your help.

Do I took the motor to a local kohler shop they looked the carbs over and everything checked out. He called kohler and kohler suggested adding an external fuel pump I picked the motor up this morning it seemed to run fine when at shop, but after getting home it is running better however, I can still notice at idle and droppin it full throttle it will still strain. However, if I feather on the throttle it doesn't seem to cause any issue not got to run it yet.

If you are using quick connects at the tank, get rid of them. Just push the hose up on the nipple and hose clamp it tightly in place. If you are not using quick connects and already have the hose on a nipple and clamped, make sure that the nipple is not too small. Are you sure your primer bulb is pushing fuel the correct direction? Have tried a new primer bulb? Many have had leaky primer bulbs. I don't think the 9mm fuel line size is a problem but 1/4" is recommended by PD. Another thing--Is the vent cap on your tank loose? It should be loose. This is often overlooked by some.

I've run with quick connects and without...no primer bulb and with primer bulb...short hose and longer hose...mechanic said the carbs weren't getting enough gas and after installing elec. fuel pump it was pumping plenty...not sure now what's going on now...I've ruled out anything with the hose, tank vent/leak, trash in carbs, field delivery problem...am I just not going to be able to go full throttle quick from idle, and have to feather on the gas?

Had the same problem with my outboard.
I just changed the Siphon-deal inside the tank and it was fine, could be the same issue you're having..?

I've tried 3 tanks and it's doing the same thing with all three. I have no idea really not sure what to try now.

Hopefully sice you brought the motor to a mechanic he checked this:
Make sure when you twist the throttle to wide open that the choke cable is not being pulled, I had the same issue with mine and all I had to do was push in my choke knob, once I got home it just needed a good cleaning and lubrication on the linkages on the rear of the engine. If this is the problem..... Get another mechanic! Lol

Well took her out today for a duk hunt and motor didn't run too bad. Still would not consider it perfect, but definitely much better...now the bigger problem 2 people avg. weight 220 dog 60, 20 decoys, guns and 10 gallons of gas slight wind...average speed 17mph I realize it wouldn't be keeping up with the 25hp outboard but was expecting a little faster speeds. Running the 27 kohler on a 17x48 uncle j hull..love that rig not the speeds lol...any suggestions I'm limited to a 25 hp restriction here in Arkansas.

Those speeds sound about right. That's a pretty good sized hull with a good amount of weight in it. That's about what my 1648 would run with a hunting load. Add a third person and their gear and it would pretty much fall on it's face. Yours may handle the load a little better than mine with the extra foot in length. Also may pick up a little bit by moving some weight around.

My advice, turn the mph setting off on your gps and be happy you are on step and chugging along at a decent pace...