Want to swap my 6.2 hard to start

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josephjoe

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I have a 1982 c30 it's a towtruck rollback deck
It has the 6.2 manual with pto and it's really hard to start like it'll take an hour sometimes. I have to heat up the motor quite a bit before it actually starts. I want to to swap it to a 350 it'll be more mpg but I can actually start it when I need too. I just thought I'd get some input on whether to actually change the motor or what I should swap it too I was thinking regular old carbed 350 or 350 tbi but everyone's telling me if I'm going to wire in a tbi I might as well put in a ls. Also would a 350 just bolt right up like could I just the same clutch from the 6.2
 

Blue Ox

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I'm going to regret this, but have you diagnosed the hard start, or you just don't want the diesel?
 

aasleson

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When I first picked up my CUCV, it was hard starting even in the summer it needed ether to get going. Since I use it as my plow truck, reliable cold starts were a must.
I ended up swapped in dual Group 34 batteries. Upgraded to larger battery and starter cables. installed a new gear reduction starter. replaced all the glow plugs. added fuel check valves — one between the fuel pump and filter head, and another between the filter head and injection pump to prevent drain-back. I also make it a habit to put in a fresh set of glow plugs before each winter, and ever since doing all this, I haven’t had a hard-start issue
 

TotalyHucked

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I had to double check where I was, suddenly it sounds like Facebook in here :hidesbehindsofa:

OP, first I encourage you to do some research, it doesn't sound like you've done any at all. It's not hard to swap in a 350 in place of a 6.2 but there's lots of little things that have to change, it's tedious. It's well documented on the web. I would first start by diagnosing what's causing the long start with the 6.2. Yes, diesels can take a bit to crank in cold weather but it should only be a few minutes, not an hour.
 

squaredeal91

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Im running a 6.2 daily for years and It has been hard starting before I replaced some fuel hoses and relocated my electric fuel pump. Now if it turns over good it will start every time. Most of the hard start 6.2/6.5 problems are preventable like others have mentioned. If it doesn't smoke a bunch when its warm then its probably not the engines fault for not starting easy.
Ods are you might just need a new/rebuilt injection pump to freshen it up. There's not too bad to change out.
 

squaredeal91

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Heres a 6.2 with 6.5 turbo kit on it. Has 6.5 injection pump turned up, Next are marine 6.5 injectors. Painted up these diesels look pretty snazzy
 

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Grit dog

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I have a 1982 c30 it's a towtruck rollback deck
It has the 6.2 manual with pto and it's really hard to start like it'll take an hour sometimes. I have to heat up the motor quite a bit before it actually starts. I want to to swap it to a 350 it'll be more mpg but I can actually start it when I need too. I just thought I'd get some input on whether to actually change the motor or what I should swap it too I was thinking regular old carbed 350 or 350 tbi but everyone's telling me if I'm going to wire in a tbi I might as well put in a ls. Also would a 350 just bolt right up like could I just the same clutch from the 6.2.
I’ll say (if you’re not just one and done posting) take a step back and figure out what you want. You don’t say how it runs, how old the pump is and whether the glow plugs work.
If it’s a good running engine you can to a whole lot for less $ and less time and less pain in the ass to just get your diesel in shape.
From your post it doesn’t sound like you’re the kind of person who wouldn’t get frustrated with all the details and cost of a LS swap. Even a 350 or similar while it will physically bolt right in, will take extra work and $ to get it all together properly.
 

82Diesel

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Heres a 6.2 with 6.5 turbo kit on it. Has 6.5 injection pump turned up, Next are marine 6.5 injectors. Painted up these diesels look pretty snazzy
UNIT!! There's a guy on FB Who built a 6.2/6.5 hybrid and ran it on Methanol? Or something. IIRC, 600hp... Dyno'd. Full Sledged BEAST 20lbs of boost.
 

82Diesel

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Figure out the issue, and go from there.
 

peats

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Fixing the 6.2 will be much faster and cheaper than any engine swap.
 

Andreas Wickman

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I say the same, I have been running my C20 1983 with the 6.2 as my daily driver for over 20 years. Rebuilt the engine 7 years ago with new rings and refreshed cylinder heads, and new injectors + glow plugs. It starts always after just a few cranks, but yes, manually controlled glowplugs are necessary. Press the button and count to 6, fresh batteries, and it runs smoothly with no smoke. I love that engine and its low fuel consumption.

All the best from Sweden
 

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vr1967

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Didn’t read all the replies so may be resaying something others have said, but here goes…..

You speak of changing the motor out, yet, have not mentioned any form of troubleshooting the long crank times.

Here is where I’d start.

1st, is your glow plug system working? The 82-84 glow plug controller is a known weak point. If it is bad, I’d update to the 85-up controller.

2nd, are your glow plugs good? Several replacement brands just do NOT last.

3rd, are your injectors leaking down, pump weak, or getting air into the fuel system?
 

Craig Nedrow

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