Type 4 engine question (1.7 or 1.8)

[lawryrg]

Greetings all,
I have a 79 Westy I am making my DD. The bus came with a very tired (but working 1.7 motor (very low compression and 3 broken valve springs so far on cyl 3,4).
I have not dropped the motor yet repaired the valve springs with her installed (painful but dooable).

I ALSO have a 1.8 motor on a stand thats never been run. No history on it but very dirty and some terrible looking crud (likely water in the oil) inside.

I want the best motor I can pull together from these two.

Question: should I get new 1.8 cyls, rings, heads and install them on the 1.7 block or the 1.8 block? I have no knowledge of the internal crank, cam or bearings in either engine but the 1.7 in the bus runs with very low compression.
Also planning to upgrade back to dual carbs from the weber progressive.

[Wildthings]

If you have no knowledge of the conditions inside the engines we can't give you an answer worth as much as a piece of chewing gum.

[Alan Brase]

If an engine is stored so that it gets water into it, it has very likely rust on the crank journals or other VITAL components.
It is absolutely imperative you totally disassemble it. Perhaps if the rust is very thin, the crank could be polished and possibly even reuse the bearings if they are really nice. (but not usually!) Rust is harder than steel and it will ruin the soft bearings in seconds.
If you can change the broken valve springs, that might be a plan. BUT WHY are 3 valve springs broken?
keep in mind, the horsepower of ANY of these 3 different size engines is nearly the same.
My very best bay window experience was with 1978 bus and AFC injection on a 1970 411 high compression long block. It ran great. That motor has 85 hp SAE. (Yes, I cut open and drilled and threaded the bus type oil fill hole. )
_________________
Al Brase
Projects: 67 sunroof bug, 67 Porsche 912 Targa, 70 Westy
Dec 1955 Single Cab pickup WANT 15" BUS RIMS dated 8/55, thru 12/55
To New owners: 1969 doublecab, 1971 Dormobile
Vanagons:
80 P27 Westy JUL 1979, 3rd oldest known US
83 1.6TD Vanagon, 87 Wolfie Westy daily driver, swap meet home

[P24p1]

Both of them need to be split open and examined further

But if I had to make the choice between the 2, I'd go with the 1.7l. Mainly because you know it runs and probably has no rust from internal water damage.
_________________
1973 Westfalia named Angie

What rust?

Rev it - don't lug it!

[SGKent]

broken valve springs are really quite rare. They break from either extreme fatigue or someone nicked them with a tool. I would do an extra careful inspection before putting money into those engines.
_________________
“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[oscarsnapkin]

I think (someone will certainly chime in) that a Type IV engine case is not made of magnesium like a Type 1 engine. However, I know from experience that water inside of a T1 case will destroy both the case and the internals (bearings, crank, oil pump etc…) Hopefully a T4 is more resilient.

_________________
- 1977 CEI Sunroof Bus 2.0L F.I. Hydraulic Lifters
- 1973 Thing

"It’s so easy to laugh, it’s so easy to hate, it takes strength to be gentle and kind."

[SGKent]

water will conduct electrons which then transport the aluminum molecules. Electrolysis sets in. I took apart a Maserati engine once for a friend who bought it for restoration. The Aluminum heads were like swiss cheese, unusable. That is why there are special chemicals in the anti-freeze, and we change it ever so often.
_________________
“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[timvw7476]

those lower cases 66mm crank are the same. just use 1800cc pistons, rings, cylinders & the bigger valve heads from 1800cc (if they're the '74 dual carbs).
And good to run.
The broken valve spring may just be fatigue/use. The 1700/1800 do rev out higher than any later 2.0L. All this stuff is old so what do you do?

edit: there's also a 96mm piston kit for those, from AA Piston out of CA.
a little bigger as well, but the 1800 revs so well, I do not know if more piston mass is preferable. The 1800 Type IV is my favorite Type IV size. Revs, acceleration & mpg if you can keep from spinning it on the highway.
The 2.0L really favors the campers with the pop top drag & extra weight.

[P24p1]

[Vanapplebomb]

[Wildthings]