1997 c1500 turns over but no start

[bipshoft]

I have a 1997 c1500 witha 5.7l engine
had problems in the past of this happening and changed rotor, cap, and wires
now after some really decent snows and damp weather it is doing it again
occasionally tries to fire but mainly just turns over

I am guessing something is damp and causing the issues again
any ideas on best place to start

I did try a bit of starter fluid in the TBI and no go
trying to find my code reader as we just moved but no luck on that yet

thanks

[bipshoft]

Got her going, changed the cap and rotor the other day in the freezing rain and she fired up

[tony1113]

i would reccomend sealing up your distributor cap with some RTV clear silicone. the GM caps are nutorious for getting moisture under the cap. i had the same problem with my truck...it would run great for 3-4 months after i changed the cap then all of a sudden it would start missing and not running good at all.

[j cAT]

Originally Posted by bipshoft

Got her going, changed the cap and rotor the other day in the freezing rain and she fired up

I would not use RTV silicone sealant on the cap .

what to use is silicone DIELECTRIC GREASE . COAT THE BOTTOM OF THE CAP SEATING SURFACE . remove plug wires at cap ,put some grease in the plug boot. do the same on each plug wire boot.

cap/rotor replacement every 30-50,ooomi is required anyway.

[tony1113]

i know many mechanics in my area that use RTV to seal up the dist. cap and have been doing so for a while. As long as you put a thin line (and dont go over board) around the base of the cap then you should be fine. i deffinitly use the dielectric grease on my connections between my cap and wires and then again between the wires and spark plug. the problem i found with using the dielectric grease on the seating surface is that over time it will wash away whereas RTV will not. It fixed my problem.

[j cAT]

Originally Posted by tony1113

i know many mechanics in my area that use RTV to seal up the dist. cap and have been doing so for a while. As long as you put a thin line (and dont go over board) around the base of the cap then you should be fine. i deffinitly use the dielectric grease on my connections between my cap and wires and then again between the wires and spark plug. the problem i found with using the dielectric grease on the seating surface is that over time it will wash away whereas RTV will not. It fixed my problem.

the reason I don't like the sealant is when the cap requires replacing you must be very though on removing all this old RTV sealant.

On my boat engine I had issues of moisture in the cap , this caused alot of ignition/starting problems, lots of mositure .


got the idea from boat mechanics. silicone dielectric grease. on base of cap , coat the wire surfaces with the small amount , use inside the wire boots.

so I also did this with the land based engines.

over a few decades I have yet to see a failure.wires last forever. the cap however does wear out but no arcing damage.


when I purchase a new vehicle zero miles , this is one of the prep jobs I do .

I have not experience this grease washing out from cap base.

I also don't wash my engines, some do , if so I can see how the grease gets washed out..