1998 Chevy Silverado 305 350 swap cranks but won't start.
Asked by 98silveradochev May 12, 2015 at 07:05 AM about the 1998 Chevrolet C/K 1500 Silverado LB RWD
Question type: Maintenance & Repair
I've replaced distributor cap, distributor coil
ignition module . It just isn't getting any
spark from the plugs I took screwdriver and
placed in the plugs and grounded it with
engine and turned the key but nothing.
checked for damaged wires but nothing
either. I replaced 305 because of oil mixing
with water. The 350 block came off a late
80's suburban. Also replaced timing chain
cover and sensor. Any ideas. It's my
everyday truck. And a note it was a police
packaged truck it wouldn't never start
without 2 1000 cranking amp batteries.
32 Answers
Is it the 5.7 vortec engine?
Do you have that pass lock security? Turn key to the ON position, is the security light flashing or does it go out?
http://easyautodiagnostics.com/gm/4.3L-5.0L-5.7L/how-to-test-the-icm-1
98silveradochev answered 9 years ago
It's a 5.7 . The security light turns off . It is not a vortec the engine is a 350 out of a late 1980's Chevy suburban. But the 305 was a vortec I just swapped everything over to the 350. The distributor is giving out any power to plugs.
Unplug your MAF and crank it over. See if it will run for a couple seconds.
98silveradochev answered 9 years ago
Nope just keeps turning over I double checked the spark for distributor coil theirs no current going through
It may be your distributor shaft could be 180 degrees off. Put no. 1 TDC and pull the shaft up slightly and turn it 1 slot at a time till its exact opposite from original spot. this is a common mistake because there is TDC for both intake and exhaust stroke and when first installing a distributor you're either 180 degrees off or dead on. And being 180 off won't trip any codes because every thing is working properly, just your firing at the exact opposite time that you should be. And a timing light will still show your timing to be exact. Just another thing to try........
If he was 180 out it would still spark. Was the 350 fuel injected? The 98 system requires a crank sensor and a reluctor ring for it to read. If both of those arnt there you get no spark.
Just checked chevy started using the crank sensor in 94. Your 80's engine won't have one.
98silveradochev answered 9 years ago
I took the plate off the front and put the ring on the front of 80's engine. I took exactly everything off the 98 305 and put it on the 350. I've bought brand new sensor s but still no spark repositioned the distributor. Is there any way around this at all.
You used the heads, distributor and intake off the 98? Have you changed the pickup coil in the distributor? Also have you checked your fuses?
98silveradochev answered 9 years ago
And the truck will not turn over without 2 700 cranking amp batteries. I tried just one and rewired starter before just another question and the truck has the police package on it as of the computers and stuff.
Read this link to the end. This guy had the same problem as you. Turned out to be a bad pick up in the distributor. Not sure if you've tested it or not. Might be worth a read if you haven't already read it......................... http://www.hotrodders.com/forum/hei-distributor-no-spark-think-i-tried- everything-162332.html
98silveradochev answered 9 years ago
I wouldn't think so either but it won't turn over with one battery. Everyone I know tells me that is strange and so do mechanics.
98silveradochev answered 9 years ago
There is a black wire with white stripe that is disconnected itS near the Distributor. Could that have anything to do with it I think it's a ground not sure though
does it look like a bolt goes through it? If so it's a ground.
98silveradochev answered 9 years ago
Yeah it was I put another ground terminal on it egn 1 fuses is blowing does that have anything to do with starting the engine
98silveradochev answered 9 years ago
It's not a short I just found what it was it's the catalytic converter plugs on exhaust it was wired the right way so that doesn't have anything with the distributor does it if it isn't plugged in or does it ?
Not sure about a Chevy, but when my O2 wire melted on the exhaust and broke, the truck shut right off as I was going 65 mph down the highway. So on a Toyota, yes, the O2 must be hooked up, but not sure about yours.
98silveradochev answered 9 years ago
If the reluctor wheel isn't the same does that cause it not to have spark to plugs
http://www.hotrodders.com/forum/305-vortec-harmonic-balancer- 205893.html
I think that above link will not take you to the right spot. I will try to cut and paste the info for you. Here's the original question: Will a Harmonic balancer from a 305 vortec engine work on a 350 carburated engine? Answer: Yes, it will physically fit the engine and it is also neutral balanced like the carbed 350 engine- but some of the Vortec engines use a reluctor wheel behind the damper (seen on the left, below). The Vortec damper from a reluctor wheel-equipped engine is shorter by the thickness of the reluctor, so if the Vortec reluctor damper is used on a non-reluctor wheel application, the damper could go on too far and the pulleys might not line up, and the damper might even bottom out on the timing cover. The crankshaft gear also won't be "sandwiched" between the crank and the damper snout. You could make a spacer by cutting down a reluctor and things might work out OK- although I've not tried this yet. Some Vortec engines don't use the reluctor wheel. On those engines, I do not know if the damper is longer or if there's a spacer used. If you have access to the 305 engine, look to see what it uses and compare the lengths of the damper snouts. I know this article doesn't say anything about spark issues, but it does show that there's a difference in the thickness of the Vortec 305 and the older 350. Not sure if this will shed any light on things.
Most police cars or vehicles used two batteries due to long periods of time sitting idling and the lone battery would not charge up, or the engine shut off and a lone battery would run down. A second battery was used to run all the electronic computers, radios, blinking lights and spotlights. The other ran the car but they were all charged off the same system. Make sure when the motor was roved there was not cross wires that were cut so you're not getting any power to the distributor. Start with electricity coming into the distributor. If you have it there, is there power going to a "good " coil and back to the distributor? If the electrical power is coming into the distributor and into the coil and back to the distributor, then the cap may be bad or the connections to the wires are bad. Follow the flow until you can't find it. Then go backwards. Stronger heavy-duty starters do not require two batteries. If you're not getting power to the distributor, go to the switch. Like I said, work from where you have power and follow it to the end of the power. Is your distributor turning when the engine turns? The fix sounds simple, it's just hard to eliminate everything. Yu know it will be the last place you look.
There is a chip under distributor check it is it 2 or 3 wire if its bad no spark the eighty should also have one
98silveradochev answered 8 years ago
Thanks everyone but I went ahead and sold both motors and transmissions and parted out the truck . About 9 months ago I only tryed fixing for bout a month ... . And when take wiring harness off the harness had alot of wires that were burnt out. That's more than likely why I was having electrical problems to begin with. ..put almost3500 dollars into it and went ahead and bought a 1988 Ford f250 idi pre powerstroke . And now currently I have a 2000 Ford f350 with the v10 in it. Still have the 7.3 idi.
Lol it was a 40 dollar sensor. In the distributor. Which also controls injector pulse number one problem no start