Engine Rebuild Options

[KMoore68]

Hi,

I have a 1977 911 S Targa that I have taken to a local reputed shop to fix some oil leaks. While the engine was out, I had them run a leak down test and the results didn't come back what I was hoping. The conclusion is that I'll need to do a full rebuild so I was thinking that I would have the following options:

1. Sell the car, as is, I'll probably get less than I would like now that I know the engine needs to be rebuilt. I doubt I'd be able to get back into the P-car market as prices are kind of crazy.
2. Plan for an engine rebuild with this shop at a cost of about $25K, I'm thinking to do some saving and planning for the next 18-24 months in preparation.
3. Plan for an engine rebuild by myself. The car would be out of operation for a while as I planned the parts and execution of the rebuild. This feels like a big step for me and would probably take a long time to complete.

Can you comment on something I may have missed or not thought of.

Kevin

[KMoore68]

Option #4: Buy a replacement engine however I am thinking the cost for either a 2.7 or 3.0 that has good leak down numbers would be similar to the $25K rebuild estimate

[Nditiz1]

Option 4 is the best approach and cut that in half and you got it.

A few recent great leak down numbered engines have sold for 12-15k. I think jvcass has one for sale right now, running ready to go.

[manbridge 74]

Start at the beginning.

What were the numbers?

Does it have visible blow by out of the oil tank?

If it runs good with no major active leaks or engine noise I’d be tempted to run it or sell as is.

[kevbo]

Ya option 4, if it’s not burning a ton of oil just drive it. and save/buy parts in prep for a rebuild a few years out hopefully

[mepstein]

If it needs a rebuild then continuing to drive it won’t really hurt it (probably) so just drive it until it won’t go and decide then. I’ve seen engines go for a long time after getting the rebuild news.

[Discseven]

Who concluded the engine needs a rebuild?

...If it was the shop urging you on in the smallest degree towards a rebuild and the shop is not owned by a relative to you, by default I'd suggest it being sales. And no offense to them---it's a given they're in the business of staying in business. Point is, if you're willing to consider a rebuild, before getting to mentally/emotionally committed to that path, next step might be to invest in a leak down tool to check the shop's findings for yourself. You'll have empirical info to consider rather than what might be---might be---the self serving input of a business.

[88911coupe]

Several years ago I knew my '88 needed valve guides since it was using a lot of oil. I like working on cars so I decided to do it myself and it was/is a 3rd car so time was not an issue. Of course having the cylinder heads redone morphed into a full rebuild and, with Wayne's book, it was very doable. I did it as a stress reliever from day job. I know I saved a TON of money even with paying to have some of the work done, specifically having the cylinder heads rebuilt by Competition Engineering and all the critical parts measured by Zim's here in DFW. I think rebuilds have gotten MUCH more expensive than they were 10 years ago so that may help in your decision. Of course you could sell the car and tell the buyer to do their own PPI and let them be the judge. I agree there may be some motivation for the shop that did the leak down to suggest a full rebuild. Nothing necessarily wrong with that, just keep it in mind. I'm just now about to drop the engine again to replace the pressure plate which I didn't do during the rebuild and looking forward to it.

[Showdown]

Whether or not the engine NEEDS a rebuild right now, starting to save for one is a very prudent idea. If it eventually needs a rebuild you'll have the money already and if it doesn't you have a pot of money to play with!

I'm always putting pennies in the jar for the 911 just because.

[Dr J]

I went for option 3 with a twist.

I did a lot myself and used pros for critical things. For example, I sent the short block to JB racing. They opened and replaced or restored whatever needed to be changed and sent me back the sealed short block. I also sent them cylinders which they cleaned, inspected and gave their recommendations.

[Cairo94507]

I reached out to Bruce Abbott (flat6pac) here on this site. He rebuilt my '87 3.2 and did a great job. You might consider speaking with Bruce; he is a great guy and knows what he is doing, having 30+ years of Porsche engine building experience.

[KMoore68]

Thanks for all the advice and ideas, just to clarify a few things:

1. I am picking up the car and will post the leadkdown test numbers and information they provided.
2. The owner of this shop is active here on Pelican.

I will work towards saving some money for whatever happens in the future, ie. rebuild or buy new engine or rebuild myself

[FA-18C]

If the engine is running reasonably well, and now billowing smoke, why not just drive it for awhile? You can take your time and plan a rebuild on your schedule and with a more deliberate budget.

[kyngfish]

Out of curiosity - what’s the delta right now between shop rebuild and DIY rebuild? Although I’m sure some of the prices have gone up in the last few years - we are just talking bearings and seals. Machine work and replacing or repairing bigger consumables, cams, rockers etc.

I feel like 6-7 years ago a rebuild was between 6-8k - is it the parts driving this huge increase or labor?

[PeteKz]

Both parts and shop time costs have gone up substantially. Or, alternatively, the value of the dollar has gone down substantially.

You didn't say how many miles are on the engine, or where the leakage was determined to go. Was it past the rings, or the valves? How much oil is it burning? What are the leakdown numbers?

If it's not burning a lot of oil, and it seems to run fine, I'd just keep driving the snot out of it, and I'd even drive MORE snot out of it, knowing that I was going to rebuild it within a a couple years!

I'd plan to get a replacement engine ready to drop in the car, swap it, then sell the old engine as a core. That minimizes down time. But maybe you're intrigued with the idea of driving an engine that YOU built? Well, then, do it yourself. Just be aware that the first time you do something, it will take a lot longer than you planned, and "plan" accordingly.

If you go the replacement engine route, you can get a core and then disassemble, decide what needs to be replaced, machined, or reused. Then take your time rebuilding it becuase the car will still be driving while you do it. That's what I did with my 1973T. And further, I would step up to a 3.0 or 3.2 engine, both to get more grunt, and to get a tougher engine than the 2.7 magnesium case. I rebuilt my 3.0 core SC engine into a 3.2 SC CIS engine for about $11,000 in parts, which included new Mahle Sport pistons, rings and cylinders.

One other thing: You live in Vancouver, BC, I don't know of good Porsche shops there (probably are some, since it's a major city), but if not, there are some excellent shops in the Seattle and north area, which is a few hour drive for you.

[Discseven]

Originally Posted by kyngfish

Out of curiosity - what’s the delta right now between shop rebuild and DIY rebuild? Although I’m sure some of the prices have gone up in the last few years - we are just talking bearings and seals. Machine work and replacing or repairing bigger consumables, cams, rockers etc.

I feel like 6-7 years ago a rebuild was between 6-8k - is it the parts driving this huge increase or labor?

Almost done... my numbers:

Parts = $10,128. (120 items)
Tools = $461.
Services = $3,860. (Head machining was major portion of this)

$14,449. (diy)

Few more odds and ends to wrap things up. Maybe $500.

Edit: engine is '85 3.2. Not tracked or run into the ground. Minor mods during this rebuild = 964 cams, SSI heat exchangers, sausage muffler (2 in 1 out)---all else stock.

.

[berndtj]

Echoing Pete. There are some good folks north of Seattle, that you may want to chat with. I had John Walker rebuild mine and am very happy with that decision.

[Nditiz1]

Discseven posted real numbers. I wonder if that is with a mag case. Machine the mag 2.7 case adds a lot (~5k) also add is Ollies extensive wait time. If it were a 3/3.2 rebuild all day and save money. As I said before you can get a running healthy numbers 3.0 for ~15k.

+1 for Bruce, he rebuilt an engine for me last year. Cost was around 5k.

[KMoore68]

My Leak down numbers are:

Cyl 1 25% Cyl 2 60% Cyl 3 58% Cyl 4 25% Cyl 5 25% Cyl 6 10%

The shop also that it seems to be piston rings causing the issue.

The car does run and drive without any issues so I think for the foreseeable future I'll enjoy it and drive it but plan for a rebuild or replacement in the future.

I'll also do some research and see if this is the original engine on the car and they may lean me more towards rebuilding it vs replacing it.

[KMoore68]

Thanks for providing this data point, would you mind posting a more detail on what the Parts breakdown works out to be?

Originally Posted by Discseven

Almost done... my numbers:

Parts = $10,128. (120 items)
Tools = $461.
Services = $3,860. (Head machining was major portion of this)

$14,449. (diy)

Few more odds and ends to wrap things up. Maybe $500.
.