Possible cracked case O-360-A1A

[59Moonster]

Anyone have any leads on a case for my M20A if I need to get one? I'm assuming its usually replaced but I have no idea. Do they ever fix those? 

[Ragsf15e]

They can be welded.  I believe the company is called Divco, but your engine shop will know.  
 

How’d you discover it?

[A64Pilot]

Cracks are actually pretty common, it’s not unusual for a case to have more than one crack, most can be repaired, but not all.

I had a couple of cracks on my 540’s case and never knew it until I sent it to Divco for them to clean, inspect and repair as necessary.

 

[59Moonster]

1 hour ago, Ragsf15e said:

They can be welded.  I believe the company is called Divco, but your engine shop will know.  
 

How’d you discover it?

Oil leaking up front. Thought it was a crank seal. Replaced and got oil on my windshield during flight. Only leaks with high RPM. He said he called a shop and once he said the generator mount was broken and replaced. He was then told it was cracked. Once it gets back to the shop he will borescope it. 

Any ideas on what this all might cost?
 

 

[A64Pilot]

To be honest unless it’s a very low time engine, I’d say your looking at an overhaul.

Engine has to be removed and completely taken apart, then the cases sent off, if they can be repaired they will be as good or better than new, but do you put old parts back in?

Labor cost wise it’s close to an overhaul.

[59Moonster]

Eghhhhhh. 
 

mid time engine. Two years ago put a whole new top on it. ;(

[Ragsf15e]

Just now, 59Moonster said:

Eghhhhhh. 
 

mid time engine. Two years ago put a whole new top on it. ;(

You will have to contact a couple engine shops and weigh your options. It can definitely be done for less than overhaul if you decide to go that route, but as noted, it’s coming off and apart.  How old is the engine in years?

[jetdriven]

1 hour ago, 59Moonster said:

Oil leaking up front. Thought it was a crank seal. Replaced and got oil on my windshield during flight. Only leaks with high RPM. He said he called a shop and once he said the generator mount was broken and replaced. He was then told it was cracked. Once it gets back to the shop he will borescope it. 

Any ideas on what this all might cost?
 

 

It quickly spirals into a major overhaul, but if you’re talking about pulling the case having it welded and reassembling everything with new bearing, rings, gaskets, it ranges from about 8000 bucks if you do all the labor to probably twice that if you have a shop do it. 

[59Moonster]

2 minutes ago, Ragsf15e said:

You will have to contact a couple engine shops and weigh your options. It can definitely be done for less than overhaul if you decide to go that route, but as noted, it’s coming off and apart.  How old is the engine in years?

I think original 1959. 1900 ish hours with a total rebuild 1/2 way through but couldn’t ever figure out why other than a used hour meter was changed and it had more hours closer to 2k. 

[jetdriven]

Now you’re talking about a narrow deck case, and 7/16 valvestems which have a 1200 TBO and all that. So it can get even more expensive quickly. 

[N201MKTurbo]

If you have a narrow deck case, you better hope it can be fixed. They are getting hard to find. 
 

you shouldn’t commit to an overhaul until you find out if the case can be repaired or replaced. You might want to look for a used engine. A wide deck engine.

You can get it repaired for a lot less than an overhaul, if you can find someone to do it. That assumes that there isn’t anything else wrong with it.

[59Moonster]

14 hours ago, jetdriven said:

Now you’re talking about a narrow deck case, and 7/16 valvestems which have a 1200 TBO and all that. So it can get even more expensive quickly. 

Seriously? I was told it was 2000 TBO 

[David Lloyd]

Correct about the 7/16 valve stems and 1200 TBO.  Vast majority were upgraded to 1/2" decades ago.  At worst it would have been done 2 years ago when it was topped.

[Shadrach]

On 5/26/2021 at 8:26 PM, 59Moonster said:

Oil leaking up front. Thought it was a crank seal. Replaced and got oil on my windshield during flight. Only leaks with high RPM. He said he called a shop and once he said the generator mount was broken and replaced. He was then told it was cracked. Once it gets back to the shop he will borescope it. 

Any ideas on what this all might cost?
 

 

It cost me $850 in 2010 to have my case overhauled. The IRAN of the internals and Cylinders cost $3200. I removed the engine myself. I paid a local A&P $500 to supervise my installation of the engine. Oil tight and running like a top for the last 11 years and 600hrs.

All in it cost me about $4600. If I’d paid someone to R&R the engine it would’ve been about $2200 more.

At the time my engine had 850SMOH. You wouldn’t believe how many “experts” (both online and around the drome) told me that my engine was trash and that I should be ready to blow $30,000 on a factory engine.
 

You definitely need to find the right person to do it. It’s a lot of work but not as much as some might tell you. I delivered my engine to the shop sans accessories in a pick up truck around 11:30 AM. They had the case halves boxed and on their way to Tulsa by 4:30 the same day.

Edited May 28, 2021 by Shadrach

[Shadrach]

8 hours ago, 59Moonster said:

Seriously? I was told it was 2000 TBO 

if the engine was overhauled in the 90s I seriously doubt you have 7/16 valves. If it is indeed a narrow deck case, I would call both Divco and Crankcase Services of Tulsa. Explain your predicament and ask for their recommendations.

[N201MKTurbo]

32 minutes ago, Shadrach said:

It cost me $850 in 2010 to have my case overhauled. The IRAN of the internals and Cylinders cost $3200. I removed the engine myself. I paid a local A&P $500 to supervise my installation of the engine. Oil tight and running like a top for the last 11 years and 600hrs.

All in it cost me about $4600. If I’d paid someone to R&R the engine it would’ve been about $2200 more.

At the time my engine had 850SMOH. You wouldn’t believe how many “experts” (both online and around the drome) told me that my engine was trash and that I should be ready to blow $30,000 on a factory engine.
 

You definitely need to find the right person to do it. It’s a lot of work but not as much as some might tell you. I delivered my engine to the shop sans accessories in a pick up truck around 11:30 AM. They had the case halves boxed and on their way to Tulsa by 4:30 the same day.

The last time I had a cracked case repaired I did the same as you and it was about $5000 to me.

I will be a bit more now. DIVCO is about $1200 and Nickson’s is about $1500. I would do Nickson’s.

[59Moonster]

16 hours ago, David Lloyd said:

Correct about the 7/16 valve stems and 1200 TBO.  Vast majority were upgraded to 1/2" decades ago.  At worst it would have been done 2 years ago when it was topped.

So does narrow body = 7/16 =1200 TBO and wide body =1/2= 2000 TBO or can you have 1/2" with the narrow body when the top was done? Asking because I did the top and wasn't aware of 1200 or this issue. So maybe the mechanic put in 1/2 (if possible) and I just don't know it. 

[David Lloyd]

The 1/2" refers to the valve stem diameter. It's one or the other, not both.  That was all changed to increase the TBO, valve stems wore then broke.  1/2" fixed that.  I had a Cherokee 40 years ago, Changed out the cylinders before we got it.  I'd be shocked to hear you had anything but 1/2" valves.

While I had the Cherokee, a mechanic from nearby Gastonia flew into Wilgrove in their Cherokee 140.  Leaving it broke a valve.  He and his father were replacing the cylinder a couple days later and told me they were going to get it home and overhaul to get rid of the 7/16" valves.

[Jerry Pressley]

An easier to find is an o-320 150 hp case.  If I remember correctly they are identical. jerry

[JamesMooney]

I just had something similar with an IO360. Costs added up quick. Case is $3-5k, remove and reinstall the engine is about $3-5k (30-50 hours were the quotes), some mandatory parts once the case comes apart $2-4k, and engine shop labor $3k. That quickly gets you up between $11-18k. The overhaul option is realistically going to be around $30k (lots of people will debate that and say you can get it cheaper, but most who’ve done it will agree - it adds up too). Tough call: fix the case for $11-18k, or overhaul for $30k. Depends on your mission and the history of the engine I guess. 

Most shops I spoke to said to stay away from Divco unless your case was new to you and this is the first repair. Anything after that and you’re looking at probably more cracks sooner than later - and all the other costs are the same anyway. 
 

if you PM me I can tell you which shops got good referrals, which did not, and give you a PIREP on the shop I used (lots of people here use them and I’m seeing more mixed reviews these days).

[A64Pilot]

What often trips an overhaul is once a mechanic opens something up. He or She is required to inspect everything prior to reinstalling them, everything must meet serviceable limits, and sometimes not everything does, even in what seemed to be a perfectly fine engine.

‘I’d be prepared for an overhaul whether that’s your intent or not.

Cost overhaul wise or operate an engine is about $15 dollars an hour, if you get 1000 hours for $12K, then those hours cost $12 a hour.

Plus your engine may be way overdue an overhaul based on calendar time. I must have missed that, did he say it was overhauled in the 90’s?

[Shadrach]

23 hours ago, A64Pilot said:

He or She is required to inspect everything prior to reinstalling them, everything must meet serviceable limits, and sometimes not everything does, even in what seemed to be a perfectly fine engine.

‘I’d be prepared for an overhaul whether that’s your intent or not.

Regulation please?  
There is no requirement to measure anything but the part being overhauled. It is fully legal to split the case and send it out for overhaul without ever taking a micrometer to the crank, cam or anything else that’s not part of fixing the case. The mechanic will do a thorough visual inspection of what is visible and leave everything else alone. Most case repairs are done without ever even removing the rods and pistons from the crank. That’s how a naked engine can be split and boxed for shipping in just a few hours.

Edited May 30, 2021 by Shadrach

[A64Pilot]

You guys kill me, I suppose the mechanic who would do that is the same one you guys say will “sign off” an annual for a case of beer right?

No, I’m not going to dig through the regs to find something obvious.

‘I’ve seen over and over uneducated people try to pick apart the FAR’s and argue well the reg doesn’t specifically say that, when the intent is obvious, I’ve even testified in a couple of trials that didn’t go well for the outhouse lawyers too, and I’ve seen some enforcement action too.

But if I were to look I believe that I would pretty easily find that I can’t install a part without ensuring it’s airworthiness first, that all it would take.

‘Then there is what’s called hidden damage, that I’m required to inspect for too.

So your the guy who damages a wing, but only wants a new skin, don’t fix the cracked ribs?

So how long have you been an A&P?

No one ever said each assembly had to be disassembled, but any part removed has to be tagged apprioately, and how is that done without an inspection?

Edited May 29, 2021 by A64Pilot

[goterminal120]

Shadrach is absolutely correct. There are common hardware parts and pieces that are one time use items, and there may be an AD or SB on a part requiring replacement upon removal, but for the most part the big pieces are not required to be inspected more than a visual if the engine is just being repaired not overhauled.                                                                                                            

    Would be a good idea since it’s torn down, maybe but there is no requirement. Low time with no issues other than a crack in the case, I wouldn’t think twice about fixing or replacing case whichever is necessary new main bearings and hardware, and put it back together. If it wasn’t broken before it wouldn’t be broken after. You don’t get any time back but it is a bunch less expensive.

 

  

[Guest]

Engines get split for cam and lifter failure or in this case for a cracked case, you wouldn’t look inside the mags, the carburetor, the starter, alternator and so on before reinstalling them would you?

Clarence