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John Harriott Member
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I finally took my 74 JH in to have the new exhaust welded and hung correctly. Car sounded ok, but next day it died. I towed to a shop that specializes in foreign cars here in Greensboro, They English car mechanic previously worked on my MG and he is good. The reason the car died was that too much oil was getting in the combustion chamber. I took out a spark plug before having the car towed, and it was covered in unburnt oil. The mechanic believes the oil is coming past the pistons. Now comes the woe. The estimate to replace pistons, rings etc is $6000.00. I cannot afford to spend this amount and I don't have the time or expertise to do it myself. The shop responded by saying I might be able to get by with just replacing the rings. This would be 3000.00. My questions are these: 1.) Do these seem like reasonable estimates? 2.) Given your experience with JHs, is replacing the rings likely to cure the problem? 3.) Does anyone want the car? If it comes down to the 6000.00 job, I will have to sell the car for parts or salvage. I would hate to do this. The rest of the car is in good shape, no rust. Thanks in advance, for any insight you can provide. John |
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colinw59 Member 
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This seems very very high to me. What about getting a used engine. That wouldn't cost anywhere this much and if your reasonably handy you could do it yourself, or have pretty much any good shop swap them over. |
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Brett Gibson JH5 20497 Member
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Sounds like to much crank case pressure is blowing up the cylinder walls, I would'nt do anything hastily, Judson Manning who live's down in Atlanta and does engines will probably post a note on just what you need to try yourself, but for $6K you could probably get a 2.2 with all the bells and whistles. Brett. |
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Judson Manning Member 
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John, Sorry to hear your story of woe, but no need to jump to conclusions. The oil could be coming from worn valve guides or worn liners. No easy way to tell but a head job is A LOT less expensive than a full rebuild. It could also be something way more simple. The expensive part is new pistons and bored liners. Add to it all the "while you are at it" items and a full rebuild can reach $6k, but that is an extra high 'safe' estimate. Most of my clients get away for $3k-$4k. You have options, so don't feel you are at the mercy of just one mechanic. I do have access to a pristine rebuilt engine with about 100 miles on it (long story). If you are interested, I'm seeing the owner tonight at the local Austin-Healey Club meeting. Send me a private email if you'd like to chat about it. Judson |
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Ron Earp Member 
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Hi John, You are not far from Judson - talk to him about a motor rebuild. He is doing mine and does great work. I'm down in Cary NC (Raleigh) and took my motor to Judson, well worth it. In fact, I'll be going down in the next month or so to get it and I have to drive right by Greensboro.....I've pulled JH motors in/out six times now so if you need some help I'm not far away. You've got options and I know of the motor that Judson speaks about, might be another one. But a rebuild from Judson wouldn't be all that expensive ($6k is very high, and if they haven't done a JH motor before don't know that I'd use them - I've done my own and there are a couple of fine points that I missed). Ron Last edited on 08-18-2006 12:46 pm by Ron Earp |
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edward_davis Member 
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Ron, would you care to share the fine points you missed? I want to spend several years reading and learning about these engines before I try to build one, and all of the stories I can hear will help. |
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Ron Earp Member
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Well, for one I didn't restrict the oil passage to the head and that will help greatly on the oil leaking problem since their won't be a quart of oil pooled up in the cam tower on hard left hand turns. Plus, it'll keep the bottom end better pressurized for a happy long life (unless some bozo puts the wrong oil apater on and ruins the motor.......) Judson did this modification on mine that is being rebuilt now. Ditch that "radial" oil pickup and get a pickup with a screen in the bottom and in the bottom only - like 99% of the rest of the cars on the road. Much less chance of the oil pickup drawing up air (still have to do this on mine while it is being rebuilt). Tired of lots of money for Lotus bearings? With a little trick Judson let me in on Chysler 318 bearings will fit the main bearings and offer a much better bearing selection at like, oh, 1/5th the cost of expensive Lotus main bearings. (I did manage to get this done correcly). Cross drill that crank, helps it live a long and happy life (Judson did this on mine). And there are other things as well that Judson and others can help you with. The stock motor seems underpreppared for hard driving as evidenced by a few folks who have munched them autocrossing and racing them (someone destroyed one last year at a historic race, overheated I understood since the stock radiator won't handle high RPM for extended times). More than a few have been destroyed due to oil starvation in corners and a few of the items above are specifically done to combat that. Ron |
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mdutch Member 
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Ron Earp wrote: Well, for one I didn't restrict the oil passage to the head and that will help greatly on the oil leaking problem since their won't be a quart of oil pooled up in the cam tower on hard left hand turns. Plus, it'll keep the bottom end better pressurized for a happy long life (unless some bozo puts the wrong oil apater on and ruins the motor.......) Judson did this modification on mine that is being rebuilt now. Ron, can you expand a bit on that mod? I sure would rather have that quart back in the pan instead of periodically landing on my garage floor! |
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Ron Earp Member
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The hole that goes from the block to the head for oil supply is like 1/4" or 5/16" in diameter. This is too large, or, maybe one should say overkill. The block has a hole and a little guide dowel right there where the two mate. By tapping this hole and fitting a plug with a smaller hole, like 1/16" or 1/8" in diameter you reduce the amount of oil going to the head but the amount is still more than enough. Less oil pools up in the cam towers, and, less oil finds its way out of your motor. This is a common mod for racing and performance engines all over that have "overactive" top end oiling systems. SB Fords, some years/castings, have the issue. My SB Ford for the Lola got plugged because it was far too large as well. Ford FE motors commonly have plugs put in the top end and on some galley areas because they push to much oil in certain places you don't want it, and not enough in other places where you do want it. Check with Judson, I'm sure he'll help you out on that stuff and other motor questions. Ron |
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John Harriott Member
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Update 1.) new rings 2.) valve job - new valves 3.) new timing belt 4.) new gas cap (water entering through old leaky cap) 5.) Stromberg rebuild I won't even mention the cost (close to what I paid for the car). But it is back on the road, The latest problem is a noisy gearshift, but I think I will live with that until the bank account recovers from the other work. Part of me says sell while it is running. The rest of me says - this car is a hoot, keep it. Thanks for all help and responses to my tale of woe. John |
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Ron Earp Member
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Well, I hope not too much. Rings at $100, plus about $600 to install and check other things. Head can be done with new valves for about $500 locally, tops. Gas cap and belt, maybe $150. Strombergs are easily rebuilt for far under $100. Flying Circus here in Durham would have done it for about $1500 I'd reckon, give or take $500. They've worked on Jensens before and are good folks. Carbs are easily rebuilt for not much cash if you need that done in the future. Drive down and I'll be happy to help you learn to do it on your own. Hope she's running well and things are good. R |
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John Harriott Member
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Multiply by 4 |
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Judson Manning Member
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So what I estimated back in August was pretty close???? Please tell me they didn't just install new rings on old pistons and worn liners... |
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John Harriott Member
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Well, the mechanic thought that the liner bores were straight enough to be able to just hone them. |
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Ron Earp Member
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I hate to hear that. Judson would have done a good motor for you and would have been less as he estimated. I'd have been happy to help you pull it and take it to Atlanta when I went down. But, water under the bridge. I hope she'll run good now and don't hesitate to email or ask questions on the board. There are are many folks here that can help you out, and many are local to you. R |
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Judson Manning Member
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Believe it or not, sometimes you can get away with a quick "touch-hone" to pull out a thou or two and just re-ring the pistons. Not my favorite solution, but it sure does beat spending another $$$$ on new pistons and matched liners. **Clarification: A "touch-hone" is not to be confused with using one of those de-glazing tools you attach to your drill. A "real" honing machine has to be used not only to put on a good x-hatch, but the goal is to straighten and de-oval the liners.** I'm doing the same thing on a "slap-together" engine for my E-prod car. I need something reliable to get me around the track (undistracted) so I can evaluate the suspension and other systems. An un-named client of mine relied on similar advice from another engine builder only to end-up with a non-running engine. Under closer inspection #3 (which for some reason ALWAYS is abused) was about .003" out of round and had .002" taper! The only down-side is a little more blow-by which may raise your oil and water temperature. Also, you'll want to watch oil contamination which only means you'll need to be vigilant in changing the oil when it turns black. Last edited on 04-16-2007 03:45 pm by Judson Manning |
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