Engine exploration...., Is this engine any good? Options

[bostonmeche]

Hi all,
Well after pulling the engine several weeks ago and asking retarded questions about push rod tubes, and oil geysers, I done n pulled the cylinder head off of #3 and #4. Having done this I was finally able to learn some things.

1. My cylinders are 96mm in dia and 76mm stroke, (I get 2.2L) Yeah! (IMG:style_emoticons/default/driving.gif)

2. My engine doesn't look like the prestine engines I see on all the Discovery Channel TV shows like Rides and Overhaulin. (IMG:style_emoticons/default/sad.gif)

So my questions to those who know.

1) Is it normal to have all this black cryosote (sp?) looking stuff all over the pistons and valves?

2) Should I just put this thing back together and quietly walk away and call the engine toast? or should I clean all the crude off and try and put it back together?

3) My compression numbers are:
Cyl #1 100
Cyl #2 85
Cyl #3 100
Cyl #4 75


4) Is this engine worth fix'n??

[bostonmeche]

Piston #3 has a gash in it.

[bostonmeche]

Cyl Head for #3 & 4

See all the crap on the valves is this normal?

[Ctrout]

Looks like any engine I have ever taken apart.

[newdeal2]

(IMG:style_emoticons/default/agree.gif)

[Brad Roberts]

That gash in the piston is where the valve has tapped it in the past. It also appears that you have 48x38 valves (I can tell by the spacing of the seats)

That compression ratio is really BAAAAD. Should be like 180 or so if somebody actually calculated the compression ratio correctly while assembling the engine.


B

[Brad Roberts]

I'm also surprised to see head gaskets.


B

[SirAndy]

yupp, 96 means you got a 2056, valves are bigger than stock.
this *does* look like a keeper!

the crud is not too bad and can be cleaned easily.
the compression is *bad*. my engine has 150-160 on all 4.
nothing a set of new rings couldn't fix.

big valves and big pistons are guud!
(IMG:style_emoticons/default/wink.gif) Andy

[914ghost]

(IMG:style_emoticons/default/biggrin.gif) No waaay...run away.
I'll do you a favor and send you a box, return postage paid, and I'll dispose of that horrible time bomb correctly. Dont take a chance....just hand it over.
I'll really be a nice guy and send you my perfect 1.8L screamer strapped to a pallet, just strap your old cursed engine in place on the pallet and install your new reliable engine..
(IMG:style_emoticons/default/rolleyes.gif)
Bob O


I took my 912 engine apart after 450 miles on a fresh rebuild and thats about what it looked like in the chamber.
Get new rings and new lower end bearings etc...what you care about is the condition of the journals on the crank. Have it chek'd (magnafluxed / mic'd / nitrided?)
new rings and bearings...new lifters if you're a spoiled rich kid.
Or if you're me run your fingernail across the journals on the crank, ANY feeling other than perfectly smooth?
No?
Put it Back together - Drive.

[McMark]

Rering the pistons rehone the cylinders and run it. What's it got feeding it? Dual webers?

Andy, he's got a 78 stroke so it really is a 2.2, not a 2056. Stoke 2 liter stroke is 71.

Bostonmeche, if you didn't fill in your location on purpose that's cool, but if you forgot or didn't realize then it's nice to know where are friends are located. (IMG:style_emoticons/default/biggrin.gif)

[bostonmeche]

So I think the general concensus is to:
1. Clean everything up (hot tank?)
2. Scrap all the crude off
3. Hone the cylinders
4. Put new rings on the pistons

markd,
The engine is fed by dual Dellorto 40's and even has anodized blue roller rockers. I actually have a 76mm stroke, though I have to admit, I hear almost no one talk about using a 76mm stroke, usually, 71 or 78. I'm starting to wonder if I measured wrong. BTW I added my location.

Brad,
Are 48x38 valves a good thing, bad thing, or just something to know? I'm still too green to understand what that implies, especially since I have no idea what is stock.
Also are head gaskets bad in this case? Should I replace them or just leave them out (the edges of the gaskets are cut up)? If I throw them out what keeps it from leaking (not that the gaskets did either)? If I leave them out, it will affect my compression correct? You mentioned compression not being calculated correctly, is that because you assumed the rings were good and the #s were bad or was there something else that led you to believe this.

Should I grind the valves too? I don't even know exactly what that means. What parts of them am I grinding?

Are these things DIY operations (ie, honing cylinders, grinding valves)? Or do I need to find someone in the Boston, MA area to do it? Also, when I put new rings on how do I know what size to order? Do I base the size on Cylinder dia or by Piston groove?

I just looked on pelican for rings $50/cylinder. Is that normal? I mean these are just flat sheet metal parts aren't they?

If you couldn't tell, the only engine I ever took apart was a Briggs & Stratton back in high school. So I appreciate all time you guys take to reply to what must seem to be pretty mundane if not common knowledge type of questions. (IMG:style_emoticons/default/pray.gif)

Wow did I write a lot! If you actually got through it all (IMG:style_emoticons/default/beer.gif)

[ArtechnikA]

let me try to be diplomatic... you are on the verge of being in WAY over your head.
take it slow, and let people help you. but you DO need to get some more background and do some basic research. if you don't have a Haynes manual - go get one. read all through the engine overhaul procedures - a couple of times - some things that don't make sense the first time will begin to as you become more familiar with the terminology.

i'm a little out of my element in dealing with T-IV's but i have learned a lot from what's been posted on this site (and others). ship off the heads to someone for a valve job. it is NOT a DIY project, even with stock parts. get some suggestions from people here who have head specialists they can trust. RIMCO is one, for street engines. there are a FEW reliable headflow performance shops if you want more. since there are but a few, they usually have backlogs, and they aren't cheap; tradeoffs...

rings are NOT just sheet metal, and you have to get EXACTLY the right size (diameter and thickness - to the 0.0001" and no i didn't use too many zeroes.) even then you'll have to fit them to your EXACT cylinder dimensions. if you haven't honed cylinders before you might consider sending those out too - it's easy to do wrong. (but the beauty of the T-IV engine is that it's pretty tolerant of minor inconsistencies - it was, after all, a production-line engine. but it will run BETTER if everything's matched.

not only is your compression pretty low, i'd want to know why it's so much lower on one side than the other. sloppy assembly could account for it but it could also be something deeper...

you're on the Internet - have a look through the Pelican tech articles and do some research on valve jobs. BUT - there is LOTS of bad information and misinformation out there - and all it takes to make it LOOK plausible is to have a nice website. come back here for The Straight Scoop - there are more experienced T-IV builders here than just about anywhere - with the probable exception of the ShopTalkForum board - and go read everything over there, too.

some of the parts are expensive and can be damaged by inexperienced handling.

you're doing the right thing coming here and asking questions, but IMO you need to do a little more research to make sure you're asking the right questions and in a position to really understand the responses.

stick with it, take it slow, get answers and suggestions, and you'll be fine.

[McMark]

Good advice. I agree 100%.

[F4i]

(IMG:style_emoticons/default/agree.gif) Tom Wilsons book is a good read as well.

[bernbomb914]

Has the engine case been machined to give the rod clearence? you have to create clearence if it is a 78 stroke I dont know if it is a 76 stroke. I wnted to build mine with a 76.4 stroke but couldn't get the crank, so I went with a 78.4. I would be interested in your engine if you decide to sell it, but properly done with the right cam and lifters it should make a great engine.

Bernie

[McMark]

78 doesn't need machining (or very slight), so 76 definitely won't. Plus it was running before, so it's not a problem on this engine.

[anthony]

Does squirting oil in the cylinder when doing a compression check work on type IVs. I never hear of anyone doing this on type IVs.

On my old bmw 320i engine it was recommended that one do a regular compression check and then redo it after squirting some oil into the cylindner. The theory is that if the compression reads higher after a squirt of oil then you know that you're loosing compression through the rings and not the valves.

[McMark]

The oil will sit on the bottom of the cylinder and not do much. The BMW has relatively vertical cylinders to oil will distribute evenly around the ring and help seal.

[ArtechnikA]

Does squirting oil in the cylinder when doing a compression check work on type IVs. I never hear of anyone doing this on type IVs.

On my old bmw 320i engine it was recommended...

it's not as effective on flat engines, which is why a compression test is typically followed by a leakdown test to determine the extent of the leaksge and - by listening to the escaping air you can tell the location of the leakage.

[SirAndy]

yupp, 96 means you got a 2056

oops, my bad, guess i should have read the "76 stroke" part ...

(IMG:style_emoticons/default/wink.gif) Andy