very frustrated
 

Hello everyone, I've been issues with my 71 suburban. I know its a combination of a lot of little things but I need some advice. Can bad timing- Carb tuning cause the engine to kick back when I go to start it? I have a problem with the starter engaging the flexplate I've tried 3 different ones and they seem to work for a couple of days then they either grind or stick to the flexplate. It happens more when the truck doesn't fire up right away. The more I crank it the more likely the starter will grind. This morning it was really cold and the truck started then died. I was giving plenty of gas but it still died and I couldn't get it to fire up again. I know the Carb needs to be rebuilt because it leaks from a few spots but where would the best place to start be. This is my family car and right now its not very reliable. Any advice would be appreciated. I checked the block and it appears to be a 77-79 350. Thanks
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Re: very frustrated
 

I would verify that the engine timing is correct.

Is the engine fairly new/rebuilt? I ask because if it has a lot of mileage, the timing chain could be sloppy causing the timing to fluctuate.

What kind of ignition? Points, GM HEI, or after market brand like Mallory or MSD?

Automatic or manual transmission? This is so we can understand the type of starter mounting.

Re: very frustrated
 

To be honest I don't know if the engine has been rebuilt recently. I bought the truck about 8 months ago off of Craigslist from a guy in AZ. It is an automatic with a 350 tranny, the hei ignition appears to be stock. I had to pull out and reinstall it because it was turned way clockwise just to run decent when I got it. It smokes a little while idling from the drivers side pipe. The timing is at 12-14 degrees. Any lower and it idles like crap and is non responsive. When I set the timing I disconnected the hose from the distributor and capped it but the timing stayed where it was at, so I set it where it idled ok. The truck looks like it sat for a while and the guy cleaned up what he could to sell it.
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I think Vectorit may be correct. It sounds like a higher mileage motor that could be having some problems. I would do a compression check then check the timing chain for slop. Once you know what you are working with you can start moving on to other possibilities.

Re: very frustrated
 

UPDATE.. I had a mechanic take a look at my truck and confirm what I suspected. The flexplate is shot, the carb needs to be rebuilt or replaced, the timing is off and the vacuum advance isn't working, plus my oil pan is leaking and when I do get the truck started it smokes out of the drivers side pipe. He said the carb may be causing the smoke but id have to get a good carb on it to confirm. I still haven't run a compression test but I hope to do so this weekend. I have the oppurtunity to purchase an engine with a new edelbrock carb, new flexplate, new oil pan and some extra parts for a very good price. It would solve 3 of those issues right away but I'm not sure how to tell if that engine is a freshly rebuilt or low mile engine, or if someone just cleaned it up to sell. I know just on the new parts it comes with its still a good deal. Any advice will be appreciated. Thanks.
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Re: very frustrated
 

You might want to make sure the blocked isn't cracked down by the starter and causing the problem.

Re: very frustrated
 

Do you mean unbolt the starter and check where it mounts for cracks? I have removed that starter a lot and never noticed anything but then again I never thought that may be the cause. Thanks ill check it out.
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After some research it looks like you need to check for cracking around the bolt holes for the starter. There originally was a brace coming off the motor that attached to the starter to prevent this from happening but most brackets have been removed over time. Someone correct me if I am wrong.

Re: very frustrated
 

You are very correct on the cracked starter mounts. I've seen a couple of these, and seen some of the damage it can do to flywheels/flexplates. LMC Truck sells the starter to motor braces, but they don't look like the factory braces I've seen in the past. I guess look don't matter as much as long as they serve their purpose.

Re: very frustrated
 

Update. The deal with the engine fell through. So it looks like I'm gonna have to do what I can with my engine. Is there any way to get to the flexplate without completely removing the transmission? If not do I have to remove both drive shafts or can I unbolt from the rear end and slide it back?
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On the two piece drive shaft it most likely has a carrier bearing so if you unbolt that and from the rear end you could slide the whole driveshaft back. Or just remove the front portion of the drive shaft though it can be stubborn when dealing with the carrier bearing, its a good time while you have it apart to check it and all your u joints. Removing the flexplate will be easiest if you drop the transmisson. you might be able to unbolt it and slide it back but if it was me i would drop it and make use of the extra space to get the bolts out that hold the flexplate to the crank. Or you could just pull the motor and leave the transmission which would allow you to check the timing chain and other issues while your at it. Hope this helps. Welcome to the board.

Re: very frustrated
 

When I had my trans out for a rebuild and new clutch, I had to pull the 2 bolts that hold the carrier bearing to get enough clearance to get the driveline out. That may be different than yours since these trucks came with a few different carrier bearing designs. It was no big deal for me since I also replaced the carrier while I was under the truck.
Racer2172 is correct though... You either drop the tranny, or pull the motor. Besides checking out your timing chain and such, pulling your motor will allow better access to the starter mounting holes should you need it. And if you have a leaky pan gasket, this would also be the time to change out that (and take a rare peek into your bottom end to check out the health of that).
But then there's something to be said for dropping your tranny too. Most shops will do a re-seal for less than $200.

Options....

Re: very frustrated
 

I went home for lunch and was able to unbolt the carrier bearing and got the driveshaft out. I put a baggie on the rear of the tranny to contain some of the fluid. I don't have a hoist to pull the engine so I have to do what I can from below. I loosened the hoses to the tranny cooler and left back to work. Tonight I'm hoping to unbolt the tranny from the engine and possibly get it on the ground. Is there anything I should be aware of? This is the first time I do any of this. Thanks for your help.
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Re: very frustrated
 

Make sure your tranny dipstick doesn't have a tab bolted to the back of the head like some do. Also look for the vacuum line on the passenger side that goes from the carb or manifold to the vacuum actuator on the tranny near the tail shaft.
Make sure you slide the tranny STRAIGHT back until the input shaft (the shaft that sticks out of the front of the tranny into the torque converter) is free of the torque converter.
Oh, almost forgot, put a jackstand or blocks under the back of the oil pan so the engine doesn't rock back and break your dist. cap against the firewall. There's not alot of space there with the HEI style cap.
I'm just hangin' around the house tonight, and I've been where you are. If you need someone to talk you through something real quick, call me... 530-305-8506. I hit the sack around 9 to get up early for work, but I'll be availible til then.

Re: very frustrated
 

I've never had to do what you are about to attempt.

But here are my .02

I would un bolt the torque converter, then take some wire and try to secure it snugly against the transmission. You don't want it to disengage from the pump housing inside the transmission while you are wrangling the transmission around, then causing more headaches when you go to re assemble every thing (meaning that the TC becoming disengaged from the pump, and not letting you put everything back together easily).

I may be over thinking that, so someone else may chime in with clearer more experienced thoughts.

pull all the spark plugs out, so that you can turn the crank easier.

make sure to disconnect the reverse light wire, trans linkage, and vacuum line.

You may want to get a jack with a piece of wood to support the engine, put a tiny bit of upward pressure on the engine before you try to move the trans backwards. This should keep the engine from tilting back enough to cause you trouble.

Re: very frustrated
 

Thank you vectorit. Yes wiring the TC to the tranny would probably be easier. Takes some thin wrenches to get into the TC bolts though.

Re: very frustrated
 

A lot of rental equipment places, rent engine hoists and transmission jacks.
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Re: very frustrated
 

You guys are awesome. So far I've pulled the distributor. I will pull the plugs linkage and start on the torque converter. Thanks guys ill keep you posted.
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Re: very frustrated
 

something I came across on the internet (so it must be true) sbc had metric starter bolts on the later blocks (gen IIs?) they were slightly different diameter wise, if you mixed them up, the extra side play from the smaller diameter bolts will allow the starter motor to cock. I guess there are adaptor sleeves you can use to correct this.
(The starter bolt shoulders are knurled so they fit the bolt holes snug)-just something else to check, wont cost you anything- you may have gotten an oddball part (re-man) somewhere, it happens. Good luck. Usually a kickback= too much timing, too far advanced.Check you plug wires unless she runs real smooth-

Re: very frustrated
 

Hey everyone, so here's an update. I ended up pulling the engine and tranny out to replace the oil pan gasket and flexplate. Once it was out we saw the heads needed a valve job and the bearings were pretty scuffed. So off to be rebuilt she went. Money's been tight so I spent what I can cleaning up the engine bay and cleaning all the accessories because I can't just go buy everything new. Long story short, engine is in looks good and I just have a few loose ends, mainly a freakin starter that refuses to mesh with a flexplate. That was the original problem. I purchased a starter bracket from the oc truck shop and the holes don't line up. I'm drilling a hole into that bracket to see if I can make it work. I've been working on getting it drivable for the past week straight after work. Any advice will be appreciated.
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Re: very frustrated
 

There are two flexplates that typically bolt up to SBC. There's not a huge amount of difference between them size-wise, so you may have the larger one and a starter designed for the smaller one. Or the bracket is designed for the smaller one. Either way, the problem is the same. I'm pretty sure the starter would use a slightly smaller gear to engage the larger flexplate. If you still have the packaging for the flexplate (assuming you bought a new one), check to see how many teeth it has (153 or 168). Then make sure you have the right starter for for that flexplate.

Re: very frustrated
 

Last night I took the passenger side header off to get the bracket on. I got it bolted up and tested the starter. It sounded ok. It wasnt grinding but I did notice that the bendix gear was not retracting all the way after cranking. It would sometimes but other times id have to push it back with a screwdriver. I am trying to get the shimming correct but I'm not sure how to only shim the outside bolt. Would you cut the shim and place it on the bolt kind of like a washer? Is the bendix going bad after all the test starting?
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Re: very frustrated
 

If you bought a rebuilt starter, the bendix or solenoid could be bad or marginal from the beginning. Typically, rebuilders test everything before, during and after assembly. But bad parts do get by the tests, especially if the rebuilder doesn't have quality in mind.
A weak bendix spring or solenoid could cause the problems you have. Also check the voltage going to the solenoid from the ignition switch. A voltage drop could cause issues that would look like a bad part.
As for shimming... Yes, you could cut up the shim. Or you could just find a washer the right thickness. But if you just have to shim one bolt, I'd be looking at why that is. Chevy starters shouldn't have to be shimmed at all. That's just how they were all designed. If you were working on a Ford, That would be another story! (Many Ford starters come with shim kits in the box. Hmmmm..... Just another reason to own Chevys?) Can you get any clear pics of the starter bolts and where/why you have to shim? If we could all see what's going on, it might be easier to diagnose the problem and get your Burb back where it belongs...On the road.

Re: very frustrated
 

I wish I knew how to put up pictures from my phone on here I can show you what I'm dealing with, the reason for the shims is that I'm going off the little 1/8 inch rod that came with the starter. I believe it goes between the bendix shaft and flexplate teeth to check clearance. With no shims there was a big gap between the shaft and teeth, I put a couple of washers on the outside bolt and it got closer. But its still not close enough and it binds. I've been reading that orileys starters fit pretty good. Should I "START" off fresh with another starter?
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Re: very frustrated
 

Let's go back to the engine and flexplate for a sec... What size engine? As I said before, there are 2 different size flexplates for Chevy engines, the 168 tooth being waaayyy more common. Also, some are drilled out with 2 bolt patterns to fit multiple applications. And there plates for internal balancing and external balancing (SBC=internal, BBC= external, EXCEPT small block 400 which is external!)
This may, or may not, be a dumb question (Like "is your computer plugged into a wall outlet and actually turned on?")... Is your flexplate installed correctly (i.e., the proper side of the flexplate facing the engine)?
Go back to the compatibility issue (Its free!)... Are the starter and flexplate compatible? If so, then look at the voltage going to the starter (Also free!).
If all else fails, look into a different starter.
By the way, posting photos is done with a photo hosting site such as photobucket, flickr, etc. I have a free photobucket acct. with a mobile ap. (Once again, free! Can you tell I dig free stuff?)

Re: very frustrated
 

Hey gearboxx, let me take a moment to thank you for your help. The engine is a 77-79 350. It has a 168 tooth flexplate.I do have it installed the correct way and I will look into the voltage before a grab another starter. I have to take a weekend off working on the truck because its getting to me. Ill start fresh next week but I will explore all options before buying another starter. I've heard that some starters have a different amount of teeth. Is that possible? Also heard that using a newer year like 94 suburban may work. Can anyone confirm or deny?
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Re: very frustrated
 

http:// http://m1332.photobucket.com....html?newest=1

Testing photo upload
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Re: very frustrated
 

http://m1332.photobucket.com/albumvi....html?newest=1
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Re: very frustrated
 

I don't remember if the different size flexplates are compensated for by teeth on the starter or mounting position of the starter. There are also at least 3 different mounting styles for Chevy starters... 2 bolt/aligned, 2 bolt/staggered, and LS series engines. The best way to compare them would be to take yours to your favorite parts guy, and have him bring all 3 out to compare to yours. Take a tape measure with you so you can pull out the starter gears and measure the throw, compare mounting points, check the gear diameters, and make sure all mounting holes are correct. You can also ask them if they'll look up the starter you have to be sure its for your ENGINE (not year/make/model of the car).
No need to thank me. I just like people to enjoy their cars and be able to use them. I'm quite often in the same boat. I don't make alot of money, work on my own cars, and need them for basic transportation. If I get stuck on a problem, its a big problem since I need my cars to get me around!

Re: very frustrated
 

Too bad you're not a little closer to me. There's a car show in my little po-dunk town tomorrow. Might get you psyched about your Burb again, and all the owners are near their cars to chat with. Nothing like a gathering of a few hundred gearheads to help answer your questions!

Re: very frustrated
 

Dude, I don't even know where grass valley is. I tried to get it going by last weekend for motivation, there was a swapmeet down here at irwindale but obviously couldn't. I got satisfaction hearing it run for about 15 minutes last Saturday, but then the valve covers, dip stick and lower hose started leaking. Besides that I think the wife is tired of all the time I'm spending with the cars. Thanks for the invite though!
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Re: very frustrated
 

Just saw the photobucket pic you posted. Looks like the angle of your starter is off by a few degrees. If you have the small bracket at the tail of the starter that goes to the block, it may be bent, or the holes off by a bit. If you are just mounting by the 2 main mounting bolts near the nose of the starter, you need to check the mounting pad on the block to be sure its square with the flexplate. If the starter is off like that because the flexplate is holding it like that, you will indeed need shims. Parts stores carry those shims in packages or loose behind the counter. They vary in thickness, so you may want to get a stack of thinner ones if they sell them loose so you can stick a couple in at a time. I wouldn't recommend using washers. Shim both bolts at the same time.

Re: very frustrated
 

That picture was taken before the bracket. So if it needs shims I have to do both bolts?
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Re: very frustrated
 

I would recommend shimming both bolts. The shims come in various thicknesses from almost paper thin to nearly an 1/8th inch. This is so you can get it just right. The starter is real heavy, and usually only held by the 2 bolts at one end. If you shim only one bolt, you take away most of the surface area that supports the starter. You also have both bolts contacting uneven surfaces and trying to "tweek" to one side. The shims are about the size of the surface area the starter was meant to contact, so you keep the structural integrity of the bolts and mounting surfaces. That means the weight of the starter will be fully supported while the engine is trying to shake it loose, not to mention a heavy dose of gravity when you go over that speed bump just a little too fast.

Re: very frustrated
 

I'm kinda late to this discussion...... It's already been established that two different size flexplates exist, but not pointed out each flexplate size requires a specific starter.... The starter for the larger flexplate has the two mounting bolts staggered, while the smaller flexplate's starter has the mounting bolts parallel...
In either design, a "high torque" starter has a longer motor body that is eaily identified by a longer "contact screw" and spacer obtaining electricity from the solenoid.

I once had a flexplate that was bent enough that it didnt run true and would pass close enough to scuff against the starter teeth. When starting from a spot wher the teeth were close, the solenoid wouldnt pull far enough to engage the starter motor, but would jam the teeth meshed and I'd have to crawl under with a screwdriver to detangle it. When starting in a spot where the teeth were too far away, i'd get grinding.

Given a choiice, I'd get the bigger flexplate and starter and start with new stuff!

Re: very frustrated
 

Ok so after countless attemps of shimming and reshimming I ended up cracking the nose of the starter. So I exchanged it for the same kind of starter, ac delco body with a cheap nose cone. It obviously didn't fit right so I started the shimming game again. I was able to get the starter shaft to within 1/16 inch from the flexplate teeth. It didn't bind and it had more of an engaged tone if that makes sense. I tried it numerous times and no binding. I think I got it. Problem is it took about 3/8 of an inch of shims on the outside bolt. I know it shouldn't be that way, but it seems to be working. I was satisfied with it and bolted the brace back up and then the header. I was able to fire it up and let it run for a good hour. I have a valve cover leak to deal with and wiring for the electric fans but that's minor in comparison. Hopefully the starter will hold up.
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Re: very frustrated
 

Have you hooked up a vacuum gauge to the engine?

Re: very frustrated
 

No I haven't yet. I have a couple small isues to take of before letting her run again. I found that my leak wasn't a valve cover, it is leaking out of the back of the intake manifold. Also the timing is off some how. It takes a couple of tries to fire up and the distributor is way cocked counterclockwise. I know the carburetor is junk so I'm just using it until I can get a new one.
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Re: very frustrated
 

Alright, the past couple of weeks have been pretty tough but I'm happy to say that my truck is back on the road. I removed and reinstalled the intake manifold with plenty of rtv, reinstalled the distributor with the rotor pointing toward no 1, installed new plugs and wires, had to get my radiator soldered and removed and replaced the timing cover gaskets and used plenty of rtv once again. I test drove it around the block Saturday and was greeted with no leaks. On Sunday I loaded the family and drove between 5-10 miles keeping it under 45 mph. I've been driving to work all week in it and it seems to be running fine except for a little stumble/surge while at speed. Does anyone know if that is common with a bad carburetor. I have the timing at 10-12 degrees. Also I noticed that it starts easy in the morning or after a long break, but its harder to start right after its been driven. Any suggestions?
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Just a minor correction. There are internally balanced big blocks (396 & 427) that share the same flexplate as the typical (non-400 crank) small blocks. They can run either the 153-tooth or 168-tooth flexplates.

The externally balanced engines (400 & 454) only came with the 168-tooth flexplates but they are different parts with different balance weights. Either will bolt up to any other pre-one piece rear main seal small or big block but is only correct for one application. I have seen 400 flexplates on 327's and non-counterweighted flexplates on 454's so you have to be certain what you have is correct for your engine.