Need Engine rebuilding advice, 1.7 top end bad, need some options |
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Need Engine rebuilding advice, 1.7 top end bad, need some options |
brandomc |
Aug 4 2009, 12:53 PM
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#1
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Member Group: Members Posts: 113 Joined: 14-May 09 From: los angeles california Member No.: 10,363 Region Association: Southern California |
Hi Everyone, I am needing some advice for what i should do with my engine. I have a 72 1.7 Fi motor with 80k on it at least. The previous owner said that he put all new seals in it and ignition components, but as far as i can tell he did nothing. He also said that it just needed a valve job on the passenger side cylinder head. Also a big lie. when i tested compresson on the engine "after buying it" i found 0 compression on Cyl # 4. I decided to let a volkswalgon mechanic i know work on it since i thought all it needed was a valve seat or something like that replaced. Oh yeah, the engine did run, but not well. Anyways, the mechanic calls me over and shows me the carnige of my top end.
It isnt too bad i guess, but the head, piston and cylinder are shot on #4. The mechanic says that he will pull the pistons and cylinders and use his extensive knowlege of the engines to determine if the bottom end is good or not without disasembling. He did that and told me that the bottom end seems solid and he couldn't see anything wrong with it. He then said that he could get all the new parts for my top end for 1500+ 2000 for labor. I feel that it is worth it to do the labor myself and i know im quite capable, i just need to know the best option for parts, or if i should just start from scratch and build a "biger" engine. Does Raby have any top end kits for something like this? Any advice is appreciated. |
aircooledtechguy |
Aug 4 2009, 04:05 PM
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#2
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The Aircooledtech Guy Group: Members Posts: 1,966 Joined: 8-November 08 From: Anacortes, WA Member No.: 9,730 Region Association: Pacific Northwest |
You NEED to pull the bottom-end apart anyway to find the chunks of that piston where the valve now sits. That is not an option. If it were. . .
A top-end rebuild is a false economy IMHO. The big expense of rebuilding one of these motors is in the top-end anyway (P&C set and heads). If that's all you do, you end up with a new top end getting it's commands from a worn-out cam and lifter set. Nothing is worse for performance and head temps than the stock cam. This is your opportunity to get a well thought-out cam and lifter set in there and fresh bearings all around. Ignoring the bottom-end will only save you about $500-$600 (stock w/ Web cam). This will also enable you to better set your CR up to 8.5-9.0:1 to work better with a good aftermarket cam. |
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