View Full Version : Crank question

01-29-13, 08:09 PM
Talked to guy selling 98 deville. Says he had crankshaft replaced and now he has broken several starters. Says starter nose cone breaks. Cannot figure out what is wrong. Paid shop to fix motor and is now at 2nd shop and is giving up. Wants to sell car as is. Seems to me a seized motor would just make starter stall? But to break starter?

Manic Mechanic
01-29-13, 09:25 PM
Not enough information to offer anything useful. Why did he replace the crankshaft? How long do the starters last? Does it ever run at all? "Seized motor"? Can the crank turn? What happens when it's cranked?

If I had to guess based on what you provided I'd say it's never ran and when cranked the crankshaft starts turning then suddenly reverses directions breaks off the starter nose and dies. Reason is that they put in a 2000 or newer crank with a different crankshaft reluctor wheel triggering the '98 ignition system differently than the 99 and older cranks would. But I would check the crankshaft sensors and wiring for correct placement first, just in case.


01-30-13, 04:31 AM
I'd also lean towards to the idea that it never ran after crankshaft replacement. The thought that it needed a crankshaft replacement from the first place makes me run from the car.

01-30-13, 10:21 AM
If it is ignition kickback, than cranking motor with ign disabled should work? Yes I am looking at car with dropping motor as plan. If it has new oil control plate, can you reuse them if motor has never fired? Or does the gasket material get destroyed if you take lower block apart?

Manic Mechanic
01-30-13, 01:09 PM
Yes if it's caused by incorrect ignition timing then diabling it will prevent the starter breakage. You guys who plan on dropping these engines for a deal are gluttons for punishment. I think you can reuse the plate because I read a old post by Jake where he said he's reused them by carefully cleaning the old sealer off and resealing them with the GM gray silicone. If it is new and comes of intact and checks out real nice, which it should, I would reuse it.


01-30-13, 02:31 PM
The sellers ad states car needs starter. Otherwise ok. I talked to him and after 3mins of rambling I told him to stop talking. Nothing a good, different engine won't fix.

01-31-13, 07:40 PM
What are the odds that the motor is mistimed and valves are hitting the pistons?

01-31-13, 10:18 PM
Given the questions raised, probably pretty good.

Manic Mechanic
01-31-13, 10:31 PM
Not very high, starters are stronger than valves and pistons. I've bent a valve on a engine while turning the crank by hand with a wrench to line up the timing marks with the head on, I felt the bump. I put the timing belt on then did a leak down check and had one leaking past the intake valve. It would have never fired that hole. I pulled the head right back off and sent it back to the machine shop so they could reset up the valve train on the head (OHC Honda). A fellow tech once mistimed one head on a Ford 5.4 and it started, hit 4 valves hard and repeatedly. The racket was horrible and he immediately shut it back off. Valve covers were pulled and damage was accessed. The affected head was removed and we found one valve blooming like a steel flower out of the piston itself. The customer who wanted to make sure his 200K engine lasted another few years by getting an overhaul got a 70K engine for the same price as the repairs and the boss lost about $2400 in parts and labor after getting paid. Good times.

If you want to break a starter you have to try to compress a liquid smaller than the compression ratio will allow, or hit the starter and get the flywheel turning then once it's going good fire one or more cylinders so far before TDC that the explosion stops the piston on the way up and forces it back down. The force against a fully engaged starter at full torque being instantly forced backwards will snap it off or at least twist or scalp the bendix. So your new found friend either has a cylinder with a lot of water or fuel in it every time he puts another starter on it or the ignition timing is really messed up somehow.

This car has a major problem, it's been worked on by God knows who that replaced the crankshaft for God knows why and it hasn't done anything but break starters since. The only thing I would consider at this point is complete engine replacement. Considering it's a '98 it would have to be a damn good one before I would get that far. I don't know how it is in MN but down here in Houston I can buy a clean running '98 for much less than it costs to put a crank in one. I don't get it. In fact would you please post the ad. I looked on Minneapolis Craigslist for the car just searching for an explanation as to why you would buy the thing but couldn't find one listed as not running needing a starter. Is it clean, low mileage and under a grand or what?


02-01-13, 01:45 PM
Just look for any cars for sale by owner. I think there are 1/2 dozen caddys under $1k. This deville is in rosemount. It's white, has a couple pics. The red deville is still at my neighbors house. 650 now.

02-01-13, 03:12 PM
I love finding cars people con't know what's wrong with and are looking to dump through frustration. Most of the time it's something simple, who knows with this one.