1978 GL1000 Will not start!

[chainsaw77777]

Hi everyone, I hope someone has an answer for this. I got a GL1000 1978 model awhile back, it has sat for 33 years before I rescued it. So far I’ve cleaned the carbs thoroughly I’ve pulled and cleaned the gastank and replaced the fuel filter and checked flow at the fuel pump I’ve checked point gap and sp gap and all valve clearances the timing is spot on. The compression is low on #4 cyl at 105 all the others have 145-150. So when I try to start it it’ll pop and backfire it absolutely will not run. I’ve pulled the exhaust and cleaned out the mouse packing. Still no luck... what am I missing?

[MikeNTexas]

are the primary ignition wires hooked up to the correct coils? reverse them and see what happens.

[CYBORG]

Conssider changing the condensers as well

[MattMcCoy]

How’s the fuel pump?

[pidjones]

He said that he check the fuel flow.

Do you give it plenty of time to fill the float bowls? I pulled mine out from two-month storage with empty float bowls and it cranked a good 45 seconds (NOT continuous!) before it fired. Warmed up, took the choke off and she sounded fine! I plan to ride her to a show tomorrow. You have to fill four automotive-sized float bowls. Also, make sure you have a clean air filter and good plug leads/caps.

[gltriker]

as pidjones has detailed above , it takes quite a few minutes of 15 seconds engine crank, cool starter motor for 3 minutes, repeat, to adequately fill the carburetors' fuel bowls. Some folks give the starter motor (and battery!) a merciful break and fill the fuel bowls manually through the fuel pump-to- carburetors "rack" fuel inlet hose barb fitting.
Open each fuel bowl drain screw to confirm that fuel is actually in the fuel bowl. Carefully, Set each carburetors' air/fuel pilot mixture screws at 3 turns out from seated position, too.

Have you seen, and read, and followed Randakk's start up preparations information?
https://www.randakksblog.com/starting-a ... ng-lay-up/

'Cleaned the carbs' is usually just good practice for continuously removing and reinstalling them until the entire fuel system is correctly addressed.

edit: I re-read your first post. Seems you have already accomplished a lot more fuel system preparation than a typical new owner has before posing their questions to the Club.

[Dr. Frankenstein]

Do you have a spark from all four plugs? Try trimming a little off the plug-end of the wires and putting the plugs back on. You do have new plugs, yes...?

[gltriker]

are the primary ignition wires hooked up to the correct coils? reverse them and see what happens.

Excellent advice. If it sounds like a shotgun blast, and the 4 spark plug wires are each routed to a proper spark plug connection, odds are the primary ignition wires correct terminal placements are reversed, or mismatched component colors' connections have been erroneously created under the rubber umbrella.

an example of mismatched wire colors?- Several years ago, a fellow was having similar noisy issues.
Turned out he had accidentally plugged both individual male primary ignition leads, from their respective breaker points, into just one of the two double female wire terminals .

Check to be sure the spark plug wires are routed to their proper cylinder number orientation, too.
- A too common Clymer's GL1000 manual, ignition system illustration error.

The right hand ignition coil services both front cylinders. #s 1 and 2.
The left hand ignition coil services both rear cylinders. #s 3 and 4.

[Sidecar Bob]

Re dry carbs: Somewhere in the information on the Randakk site he said to disconnect the fuel line and pour 180cc of fresh fuel in to fill the float bowls before attempting to start it so that you don't have to keep cranking to get the fuel pump to fill the carbs.
I've been doing that since I first read it and it usually results in the engine starting very easily. It also works for bikes without fuel pumps that have vacuum petcocks - 45cc per carb down the fuel line and you don't have to crank the engine enough to produce enough vacuum to open the vacuum petcock long enough for the carbs to fill before it starts.