Gear reduction starter failure

[petex19]

I take a big sigh writing this as I expect the worst.
I had my engine idling excellent and was getting ready to take it for a drive when the engine just stopped dead. I had oil pressure and AFR's were in the 14's so not dangerously lean. I tried starting it again and I could hear the starting spinning but not engaging. I got out of the car and could see oil pouring out by the starter. I immediately drained the oil from the engine and the oil was clean. I went under the car and seen that the starter gear came off the starter and stooped the flywheel. I noticed two of my three starter mounting bolts were loose. No idea how they got loose but they did over the years. I removed the starter and was able to remove the starter gear from the transmission bell housing. The flywheel looks to be perfect and the motor rotates as it should from the crankshaft. I ordered a new gear reduction starter from Midwest. I have replaced the starter before over the 31 years of car ownership and no oil ever dripped.
I'm afraid I have done something to the engine block. I read somewhere that it could be a rear main seal?

My plan was to install new starter, put oil in engine and do a compression test on all four cylinders. I guess I would know pretty quickly if my block is a sprinkler.
Any thoughts and please be kind. I don't think it's anything I did but I am beating myself up over it.

 

[Alex(Tenerife)]

There is an oil plug behind the flywheel, if when you start/tur it over it next you still see oil coming out, it could be from there.

I had this pop out on me and it ended up killing the engine. so make sure you don't run the engine with no oil pressure

Did you bench test the starter?

 

[petex19]

There is an oil plug behind the flywheel, if when you start/tur it over it next you still see oil coming out, it could be from there.

I had this pop out on me and it ended up killing the engine. so make sure you don't run the engine with no oil pressure

Did you bench test the starter?

Where is this plug? Can I replace it with engine in the car or do I have to pull the engine and/or the tranny?
Bench test? The starter still works but I don't trust it since the gear came off. The gear is still in perfect condition and I put it back on. I ordered a new gear reduction starter from Matt at Midwest.

 

[Alex(Tenerife)]

I confess I didn't do this, I had a garage do it for me.

However as I understand it the engine can stay in the car but the gearbox and flywheel have to come off.

 

[petex19]

I confess I didn't do this, I had a garage do it for me.

However as I understand it the engine can stay in the car but the gearbox and flywheel have to come off.

I am very intrigued and have never heard of this. Is that plug for engine oil or to keep transmission fluid from pouring out?
Hopefully someone chimes in that has a picture or video link or just information as to how to replace it.

 

[Dr.Jeff]

I believe what is being referenced here is a oil galley 'plug' at the rear of the engine block. It isn't a "service" plug like a oil drain-plug, but more like a little expansion "freeze plug" (small metal disk to fill the hole) that stays there all of the time. There are a few of them on the block. The oil galleys are the "tunnels" through the internal block that the oil flows through to circulate to all of the vital components. Therefore it is fed by the oil pump. If one of those plugs has come loose, as soon as oil pressure reaches it then oil will come leaking out.

Fiat used a couple of different styles of these plugs for various engines. And a couple of different sizes at various locations. The one at the rear of the block is usually a "dish" style (not cup). Here is what they look like:

As they are pushed into the hole the disk flattens out to seal it in place. Personally I do not care for this style of galley plug. I replace them with a threaded plug by tapping the hole. That way there is no chance of it ever coming loose. Here's an example of a threaded plug:

A little discussion about oil galleys and plugs:

Cleaning oil passages in block

what is the best way to do this? The plugs are staked, so they don't look easy to remove.

xwebforums.com

From your earlier description it is difficult to say if the oil you saw was from one of these plugs or not. You'll need to do some investigative work to find out. But there is one hidden behind the flywheel. I wasn't able to find a pic of the rear of the block to show it. But looking directly at the back of the block (flywheel off), it is toward the left side about mid way up the block.

 

[EricH]

Where is this plug? Can I replace it with engine in the car or do I have to pull the engine and/or the tranny?

Transmission has to come out and the flywheel has to come off.

 

[Rupunzell]

If this is the main oil galley plug that comes to mind, that plug is not standard. The plug is a very slightly concave disc with a ring that has been staked in place. Never like this due to the iffy_ness of the design. Historically, the "fix" has been to size (drill out) the main oil galley for internally threaded plug, then a threaded plug installed with teflon thread sealant. This will stay put, the Fiat oem design has a risk of popping out.


Bernice

 

[petex19]

Pulled transmission, clutch and flywheel and don't know what this plug I'm looking for is?
I little damage to my clutch plate and one of the clutch bolts sheared off so it needs to drilled out of the flywheel. No other damage that I can see. Please point out this plug in my picture. Thanks

 

[Dr.Jeff]

It is difficult to see in your picture, but to the left and up from the crankshaft. However if it was leaking you would see a lot of oil running down the back of the block, which doesn't seem to be the case. As I stated earlier, it's hard to say from your prior description where the oil you found at the starter came from. Please explain it more clearly; was there oil pouring out of the starter motor itself, or oil from around the area where the starter is located? The end of the oil pan (in your pic) looks really oily. Perhaps the oil pan gasket is leaking?

Was the sheared clutch bolt from the starter drive gear jamming into it? Another thought I had earlier was the starter gear may have disrupted the rear main seal somehow. But I don't see any oil leaking from the seal. Or did you already clean things up before shooting the pic?

 

[petex19]

It is difficult to see in your picture, but to the left and up from the crankshaft. However if it was leaking you would see a lot of oil running down the back of the block, which doesn't seem to be the case. As I stated earlier, it's hard to say from your prior description where the oil you found at the starter came from. Please explain it more clearly; was there oil pouring out of the starter motor itself, or oil from around the area where the starter is located? The end of the oil pan (in your pic) looks really oily. Perhaps the oil pan gasket is leaking?

Was the sheared clutch bolt from the starter drive gear jamming into it? Another thought I had earlier was the starter gear may have disrupted the rear main seal somehow. But I don't see any oil leaking from the seal. Or did you already clean things up before shooting the pic?

The oil was pouring directly below where the starter mounts into the transmission. I did drain the oil pan and remove the starter as soon as I seen the oil pouring out. I literally just wiped down the face of the block. It was almost spotless. No sign of oil pouring down it. The metal cover plate is filthy and looks like oil poured down the front of it.
You can see the damage the starter gear did to my clutch.

 

[JimD]

I wasn't sure how oil could leak from the height of the starter location. So I searched for "oil in the starter" to see if maybe the unit had some oil in it. Look who showed up at the top of the results! It's Pete from 2013!!

 

[petex19]

I wasn't sure how oil could leak from the height of the starter location. So I searched for "oil in the starter" to see if maybe the unit had some oil in it. Look who showed up at the top of the results! It's Pete from 2013!!

I don't even remember that post. Lol
I've never had that issue since then until now. I still can't find a picture or locate on my engine where this freeze plug is? Could the oil that leaked out be the rear main seal?

 

[EricH]

I don't even remember that post. Lol
I've never had that issue since then until now. I still can't find a picture or locate on my engine where this freeze plug is? Could the oil that leaked out be the rear main seal?

There are only so many possibilities for engine oil leaks on that end: the welsh plug we've been talking about, real main seal, cambox gasket, cam end plate so if it's engine oil it has to be one of these. I'm going to go with the main seal and flywheel has been slinging oil everywhere including the starter nose for a while. But check the plug too - Here it is, middle left in the photo:

 

[Steve Thomas]

the main seal and flywheel has been slinging oil everywhere

agreed

 

[petex19]

There are only so many possibilities for engine oil leaks on that end: the welsh plug we've been talking about, real main seal, cambox gasket, cam end plate so if it's engine oil it has to be one of these. I'm going to go with the main seal and flywheel has been slinging oil everywhere including the starter nose for a while. But check the plug too - Here it is, middle left in the photo:
View attachment 84052

Thank you for the clarification. I just took the best pictures I could of that area and found the only picture I could from when the stroker motor build was done and came from the machine shop. The welsh plug looks the same as it did then. I agree with replacing the main seal. I don't see any trace of oil coming from the cambox.
The grainy picture is from when the original engine build was done.

 

[Dr.Jeff]

For what it's worth, on your engine this is the plug that was discussed. The disk plug sits a little recessed into the hole. It appears to be covered with something like JB Weld:

As I said, if it was leaking you would see a stream of oil running down from it, so I don't think that's your issue.

Now that the flywheel is off, replacing the rear main seal isn't difficult. Once you have the cover plate that holds the seal removed, check to make sure it is flat before installing the new seal in it. Also replace the oil pan gasket - that may be the source of the leak.

Is it possible you are seeing transmission oil leaking, not engine oil?

 

[abarth4]

Just a dumb observation, but the starter coming loose & locking the flywheel while the engine was running didn't break the crank and cause something from the inside to make it to the outside, did it? I’ve seen this happen….

 

[Rupunzell]

Have some means to run the oil pump up to operating pressure without the motor running to check for oil leaks?
This is a diagnostic that needs to be did..

Two items in this picture..

~The JB "stick"-O, not gonna work. Question is, what's under the JB "stock"-O or what might be the surprise inside.. That plug must stand the full oil system pressure from 10 to 100 psi with some safety factor. If that plug were to suddenly escape, the risk of sudden Lampredi SOHC failure is really high.. Regardless, dig the JB "stick"-O out and plug the main oil galley properly (threaded plug with sealant).

~On the oil seal plate, there appears to be a broken washer.. Check and clarify this.. if that plate is not sealing against the block, it will leak
While on the topic of washers, why the way oversized washers on the seal plate?


Bernice

 

[petex19]

Have some means to run the oil pump up to operating pressure without the motor running to check for oil leaks?
This is a diagnostic that needs to be did..

Two items in this picture..
View attachment 84065

~The JB "stick"-O, not gonna work. Question is, what's under the JB "stock"-O or what might be the surprise inside.. That plug must stand the full oil system pressure from 10 to 100 psi with some safety factor. If that plug were to suddenly escape, the risk of sudden Lampredi SOHC failure is really high.. Regardless, dig the JB "stick"-O out and plug the main oil galley properly (threaded plug with sealant).

~On the oil seal plate, there appears to be a broken washer.. Check and clarify this.. if that plate is not sealing against the block, it will leak
While on the topic of washers, why the way oversized washers on the seal plate?


Bernice

Excellent observations! I will pull the JB weld out and see what is behind it. The washer is not broken as you'll see in my picture from a different angle. The larger diameter washers are what the machine shop installed. Would smaller washers make a difference?
I will have the welsh plug hole tapped and threaded for a plug. Anyone know what size plug is needed?
I will pull the oil pan tomorrow so I can replace the oil pan gasket. I'm ordering a full engine gasket set that comes with the rear main seal. I agree with building the oil pressure before starting the engine.
Does the cover(pointed to it) have to be removed to replace the rear main seal?